I used to. I think it was because I thought you always lost HALF your money if you were completely defeated, and I just kinda considered it "losing" the game somehow. So I always reset to my last save.
Nowadays I only do it if I know I would have beaten them if it weren't for my mistakes or luck. If I get completely trounced I'll often keep going for the EXP I earned in the fight to make the next ones easier.
But when I was younger, every time-->RESET! Anyone else?
my bigger brother told me that it would make you lose "points" somehow if you lose and you wouldnt be able to gain certain certificates or something. i was like...6 years old, so i believed him quite a long time. nowadays i only reset when i lose in the elite4