It's kind of wonderful to pull a carrot: seems almost miraculous, since you don't get a chance to watch it grow. The only problem is sometimes even big full tops have stunted little carrots underneath them. Also, each carrot plant can obviously give you only a single carrot, so they're kind of space intensive. Still, the potential rewards outweigh the downsides so we keep trying!
Sow 1/2 inch deep in rows a foot apart, and keep the seedbed moist until germination. Thin to 2 inches apart for full-sized carrots.