To improve technique and of course trying to keep all as clean as possible. I know my own limits and speed limits and so on I never play anything I'm not capable of. That wouldn't make any sense. After three years of playing I tried to play everything as fast as possible and that sounded, I would say, like shit, and I didn't realize that if I'd play bit slower things than I was capable of playing then everything would sound much better.

--Aleksi Laiho - Advice to Play By