Trimming too thin, isn't that a @#^%$#^%! I did it just day before yesterday. Tried to fix a plate that was still leather hard by throwing in a new center and compressing. Took about 20 minutes all together. Let it dry slowly covered in plastic. Today not yet bone dry, but plate was cracked. Now I have to hit myself in the head for learning that lesson so many times before, and wasting the time to fix what I could have thrown in the same time. Lesson learned for the 2000th time!
Sometimes it's hard to just toss something Pres. You put the time into creating it, and have that little bit of connection, because of it. So it almost seems like a waste to throw it. I wonder if artists, who work with a variety of media, are worse at this than those who focus on ceramics. Those who work with other media, are used to being able to fix an issue, without starting over; erase, repaint, etc. I think that mentality crosses over, despite the fact, it would indeed be faster to make ware, instead if fixing a damaged one. I would wager, production potters, would toss the damaged one in a heartbeat.
Art teachers might be even worse, as they are so used to fixing student projects, that their first instinct is to try and repair something.