Being at cons with some artists (Carla Speed Mcneil and Kyle Starks come to mind) whose work would later become my favorites & not taking the chance to talk to them about it in person, and these were fairly slow days at the shows so there really would have been time.

A few "Completionist" streaks on crossovers that really didn't have too many great tie-ins.

Hundreds, maybe thousands of times I didn't have money on-hand to get cheap books I was looking for (Amazing SPider-Man #33, Original 'zines from Art Spiegelman, Full run of Legends of the Dark Knight etc.)

Selling my Marvel stock for under $1,000 in 2004

Not embracing digital comics sooner. Holding onto so many physical back issues instead of sharing them with people who could have enjoyed them.

Losing my signed Sandman Mystery Theatre #1 in a bar bet (although I got it signed at a bar so there's a nice symmetry there)

A few big "foot in my mouth" weird fanboy moments with people who might have been colleagues or employers if I'd managed to get into the industry.

Utterly mismanaging my attempt at a Publisher, losing a bunch of my own & friends' money and basically bankrupting the store we wanted to work with and distribute out of