Why would anyone not want to roll for their stats? It's fun, just like a one-armed bandit in Atlantic City. Keep playing until you win!
The initial character statistics in D&D were meant to follow the bell curve, so that 3's and 18's were equally rare. It was very possible to roll a mage with only 12 INT, for example, which creates anxiety because you need 18 INT to cast 9th level spells, and who wants to start out with a limitation like that? But that is not really a problem at level 1, and to solve this problem for later levels, D&D offered many methods for character to increase stat scores through adventuring ... magic pools, wish spells, tomes, artifacts, belts of giant strength, etc. In other words, obtaining high level ability scores was meant to be part of the D&D reward system during play. I think that should have been explained better in the character creation section of the books.
