"For example, I...

"For example, I was taught in college that one ought to figure out a program
completely on paper before even going near a computer. I found that I did not
program this way. I found that I liked to program sitting in front of a computer,
not a piece of paper. Worse still, instead of patiently writing out a complete
program and assuring myself it was correct, I tended to just spew out code that
was hopelessly broken, and gradually beat it into shape. Debugging, I was
taught, was a kind of final pass where you caught typos and oversights. The way
I worked, it seemed like programming consisted of debugging.
For a long time I felt bad about this, just as I once felt bad that I didn't hold my
pencil the way they taught me to in elementary school. If I had only looked over
at the other makers, the painters or the architects, I would have realized that
there was a name for what I was doing: sketching. As far as I can tell, the way
they taught me to program in college was all wrong. You should figure out
programs as you're writing them, just as writers and painters and architects do.
"
- Paul Graham