What Was Your Absolute Biggest Mistake As A Beginner?

Couldn't have put it better myself

JCSF , thanks for asking. After a twenty year lull in my collecting I got back in and found a local dealer that I could go to and gain knowledge. 1988. He started bringing in the new issues of Ireland and Germany. I still visited the US Post Offices for the US new issues. By 2018 the internet had become my go to source for my specialty collections. It has been a truly great adventure.

It 100% sounds like one - Thank you for sharing!

Not starting to create and collect maxicards ASAP...

Ask not what your mistakes were, instead ask what was the BEST lesson you learned .... for me it was to forget the flash of new issues, first covers and instead pick a country, buy a Scott's specialized tot that country or group of countries and hit that country from start to 1950 and buy the best quality you can afford.

Biggest mistake was not selling all my duplicates and unwanted material when ebay became popular in 2001 to 2004 . Should of sold a lot more at those top peak years ,just held back too much .

As previously mentioned, focusing on quantity over quality.

On a related note, my biggest regret (other than not starting to collect U.S. revenues earlier, before the huge run-up in catalogue values) is not focusing on the key items first, instead choosing to get "moar stamps". Key items are keys for a reason. They hold their value and/or appreciate. Get them when you can, as you may not be able to afford them (or find them) later in life.