here is post from robert genn. i have permission to repost his column.
IMHO this is a valid point. i will have additional comments at the end.
i respect anyone who disagrees with this perspective.
i do not expect everyone to agree with me,
but this might shed some light on why i critique my envelopes.
The art of negative thinking
May 17, 2013
  
Recently,
 I had the opportunity to look over the shoulders of two painters who 
were giving demonstrations on the same day. The first was almost 
deliriously positive and bubbly about his work, his wonderful life as an
 artist and his prior successes. Enthusiastic throughout, he shouted 
epiphanies and dispensed "empowerment" like rose petals at a wedding.
The
 second demonstrator spoke less and, when he did, it was mostly about 
problems he was having with the work--and other more worrisome ones that
 lay ahead. A couple of times he got himself into trouble--but he 
scratched his brain and was able to recover. Guess what--the gloomy 
malcontent did the better painting. We all applauded when he held it up.
 There were whistles. He didn't even smile.
This
 understanding has now been backed up in a new book by former Indiana 
and Texas Tech college basketball coach Bob Knight, aided by Bob Hammel:
 The Power of Negative Thinking: An Unconventional Approach to Achieving Positive Results.
"Superiority
 and success doesn't favor good effort or self-esteem," says Knight, 
"and it definitely doesn't hand out trophies for participation. The 
mentally precise and physically fit win, while the mediocre and obtuse 
take solace in hopeful cliches."
Bob
 and Bob have come to the conclusion that if you're perennially upbeat 
you're just setting yourself up for defeat. The positive thinker, they 
think, has a chronic "no danger ahead" disorder. He's so busy believing 
in himself that he's blindsided by oncoming problems and his own 
shortcomings.
Success, it seems, favours rigorous self-criticism. Here are some other interesting items I gleaned from the book:
Never
 gloat. Don't talk too much. Don't seek praise. Failure is endemic. 
Success is being hard to please. Be intolerant of failure. The easiest 
person to fool is yourself. Know your weaknesses. Be tough. Never let 
scanty positives override glaring negatives. Don't be a good loser. 
Don't satisfy yourself by just knowing you can do it. Do it. And by the 
way, keep God out of your equations:
"So
 when I hear a guy after a game-winning home run say or gesture that God
 was on his side," says Bob Knight, "I think to myself, 'He's saying God
 screwed the pitcher.' "
Best regards,
Robert
PS:
 Positive wish: "The sun will come out tomorrow." Negative reality: 
"Yeah, and it will flash brand-new daylight on the same old mess unless 
something is done to clean it up." (
Bob Knight)
 
Esoterica:
 All my life I've noted artists who talk a good job and do a poor one. 
Perhaps it's our ego (particularly, but not always, in men) that keeps 
us on the muddy path to mediocrity. You know the type. They ask for help
 but what they really want is praise. These folks are stuck with what 
Bob Knight calls "the optimism bias." By thinking you are cleverer and 
more talented than your buddies, many a career has been blotted. My 
personal bias is that Bobs know better than everyone else. Bob Knight 
and Bob Hammel have a point. Be negative.
*****jean's comments
isn't it interesting how art and sports can be compared? on the surface, they seem so different but they are both activities that engage your right-brain AND your left-brain - if you allow that to happen. 
when i point out things that i don't like about my work, i am not saying that my art is bad or that i lack skills, i am just saying that i can see an opportunity to change something so that i like the piece better. and maybe i won't like it better after i see it. it is just being open to options and experimenting.
if you don't like options and you just want to execute projects where you know what to do and do not have to make decisions... that's fine with me. i, too, like to spend some of my time on projects that are simply focused on a pre-set pattern. they can be very relaxing projects where i enjoy the activity (the process) and give my brain a rest.