What's your biggest mistake as a stamp collector?

Purchased Scott International albums or started a US collection, especially in a Lighthouse album, not sure witch one was worst. All the remain empty spaces in my Lighthouse album are for stamps over $ 1000 , if not $ 10,000 . Expensive coils in pair. I stopped to count how much cost fill a US lighthouse album when I reached $ 750,000 

I too collect US though I consider it more out of what made sense at the time as I depended heavily on what I could find locally as the whole internet thing was at best in its infancy and US stamps appeared the most readily available and affordable through the narrow view of the stamp collecting world I was seeing at that time. I initially put my US collection in a Minuteman album but put that aside within a year in favor of a Liberty album instead. The Liberty suffices for my collecting needs once I toss in blank speedrile pages I make on my own. Truth is the Harris Liberty album remains my only pre-printed pages album I use - everything else is either pages I printed or created on my own or blank quad/speedrille pages. I've oft times considered a nicer album but the thought of transferring roughly four thousand plus stamps, blocks, sheets, etc to a new album has kept me at bay on that move.

My biggest thing with my collecting is I loathe over paying for anything... stamps included.

I hate it when I can't get stamps off paper. It is worst if the stamps are blocks, se-tenent or minisheets and I end up tearing individual stamps instead of geting the full block/strip.

My biggest mistake as a stamp collector was taking a break while I was in college. Fortunately, going to graduate school brought me back to stamp collecting and my senses.

Learned my lesson -- it will never happen again.

Welcome to the Club, Manish! One of the mistakes we all make at one time or another is spending beyond our budget.  Whether it is getting caught up in the excitement of a live auction or simply compulsively adding and adding items to our "cart" on stamp sites, I would imagine we have all experienced that particular scenario.

Wow Ron, awesome. I am tracking how much I am spending in the hope that it will curtail my spending but so far it's not helping.

My biggest mistake of my collecting life (and one I still regret on an almost daily basis) was not bringing my collection with me when I moved to Thailand in April 2005. That included everything I'd accumulated since I'd fallen in love with stamps around 1974/1975 at the age of 9 or 10 until I took a "break" circa 2001: I had amassed not only nice collections of stamps and covers/postal history that were housed in Scott and Davo albums and Lighthouse stockbooks but plenty of philatelic literature, ephemera and more -- I was a huge pack rat and not just philatelically.

When my mother passed away in August 2001, I decided to travel in her memory. We'd always been "armchair travelers"; my first stamp album was her childhood collection (1938 Scott Modern) and we used to plan trips to all of the exotic places represented within, albeit most had different names at the time than what appeared on the stamps. I traveled cheaply and alone; I didn't even think to buy stamps on the road or send postcards to myself en route (wish I had as I no longer travel at all). The collections were kept back home in New Mexico in the home I maintained there.

December 2004 found me back in the States; I was visiting Oregon when a freak ice storm hit a few days before Christmas. I was sick of cold weather and made my way to the airport where I told a ticketing agent that I wanted to go someplace really warm with a beach. I vetoed a few choices before she recommended Thailand. 

I arrived in Bangkok on December 23 and made my way to Phuket the following afternoon. Christmas Eve and Day were spent in the bars of Patong and I'd planned to recuperate on the beach on Boxing Day (December 26). I was there for perhaps an hour that morning when the first of the big waves hit. Got tossed around a bit by that one, ran when the second came in (getting as far as a walk bridge where I hung on as the waters went over me), and was in a motorbike sidecar going up the hill before the third wave inundated the area. There were two more after that. December 26, 2004, was the day that has defined my life since.

The airport didn't reopen to commercial air traffic until the following week but by then I was doing some volunteer work -- just playing games with kids who'd lost their parents that day. I returned to the States in late February but couldn't put the experiences I'd had out of my head. So I put all of my belongings into storage (including my car, stamp collections, "souvenirs" I'd accumulated on my travels to that point, etc.), and loaded a few things (mostly music) into two large carry-on bags. I thought I'd return in six months or a year and pick up on my life. 

I'm still here more than 12 years later.

I eventually got my teaching certification and I am now deputy head teacher for a large language school and agency (we supply teachers to most of the schools in the province).

When I realized that I wouldn't be returning anytime soon, I asked my sister to travel to New Mexico (from Kansas) in order to sell the things in my storage unit. She didn't have enough room in her home to keep anything for me and I thought it would be better just to let it all go. I thought I'd like the money rather than trying to store a bunch of stamps, etc. in this environment. Of course, she didn't get that much for the material (I think she just took everything to an estate agent; I remember that she was paid US $50 for my car alone!).

Probably a year after that, the collecting bug bit me again. I had to start again completely from scratch: buying Thai new issues from the local post office. My collection is nowhere near as extensive as it once was. I cannot afford the albums anymore (shipping is a HUGE cost factor -- good albums are expensive enough without having the cost double (and MORE!) for it to be shipped to me). But I'm most saddened that I didn't even think to at least bring that Scott Modern that my mom had given me more than 42 years ago that started off my love of stamps in the first place. I consider that a part of my personal history that can never be restored -- a vital link to my mom.

Yes, this is my biggest mistake I've made in my collecting life (possibly my non-collecting life, as well).

I have two. Mine are not paying attention the hobby for years on end. I tend to be cyclical on my hobbies, where sometimes it's all I think about day after day for months on end, then it "goes dormant" for a time...usually years...while I do other things. I have tried over the years to change that but I still fall into the same patterns- I just can't seem to make it work the way I want it to ideally.

Second is that I made a huge Excel chart of my collection, listing everything I had, creating a chart to document my new additions...and then I didn't maintain it. That too is something I tend to do, I start these projects and then don't keep up with them...usually because I am too focused on something else. I say to myself "I'll go back to it" but I don't, and by time I want to it's too late and the information has left my head. And since I didn't document it, it's gone forever.

I did the same thing, too, Al.  When I first decided to get back into classic worldwide collecting, I bought an old album full of stamps on eBay.  By the time I got a close look at it and went through everything, there really wasn't much value there.  What higher CV material was in there, turned out to be mostly damaged.

I have been very cautious about purchases like that since then.  Nowadays, I will only be a collection or an album full of stamps if I can inspect it in person to get a better idea of the condition.

I wish I had started creating maxicards/maximum cards when I was a kid...an educational project.

Gladly, Beryllium Guy! The first maxicards were created more than 100 years ago, depending on who you ask...
But back then you only had a few stamp designs concordant with existing postcards, such as Egyptian pyramids, and kings/queens.
NOWADAYS is the golden opportunity to create your own personalized stamps, postcards, even postmarks --therefore your own maxicards.
There are many tips and tricks about maximaphily, but basically you pursue a postmark to be applied on a stamp on the picture side of a postcard. Those 3 elements should be related, but the images should not be identical. Visit maximaphily.info, for example.

9/11/2001 WTC, Rescue dog. I designed the stamp and the postcard, at Zazzle. Then I got the postmark from NYC: 9/11/2011!

Sorry to hear it, TinMan, but thanks for chiming in on this thread.

I do not have a US #121 in my collection either, in any condition.

A commonly seen cutoff date is 1952, the date of the death of King George VI.  Stanley Gibbons used to have a worldwide British Commonwealth "classics" catalogue that ended coverage in 1952, although I see on their website that they now have extended that to 1970!

Ryan