It's not for everyone, but deveoping a character from scratch is often more fun than starting at 6th level.
Especially for someone's very first PC, earning your stripes and paying your dues is a lot more fun (IMHO) than having everything handed to you. Also, you really learn what everything means and how to use it, when you slowly and laboriously accumulated each power and piece of equipment. A neophyte with a 6th level cleric isn't going to be very good at playing at a 6th level cleric . . . a neophyte with a 1st level cleric will figure it out fast.
Which reminds me, in the Temple of Elemental Evil computer game, 1st level or NPC were the only ways to get characters into the party. I started 1st level characters into 5th level or so parties in that -- including a 1st level cleric who basically just summoned or healed for a while.