Saying no to preschool was right for our family. These were our reasons:
1. No one in our family has ever been to preschool. Hard to see a 'need' for something we've never needed before.
2. Our oldest son is profoundly gifted...was reading at the second grade level at age 3. We felt very, very strongly about his self-perceptions NOT revolving around his smartness. Keeping him home (and homeschooled) achieved this goal. He is now 9, and academically he is 3 years ahead of his public school peers. He's not a 'nerd' or a 'bookworm' or whatever label he might have worn. He is an activist, an athlete, a naturalist, and a boy who likes to read. I think it would have been hard for him to feel accepted and well-rounded in school.
3. Our second son has ADHD. We choose not to medicate him, and it was a scary choice. He couldn't tolerate Sunday school, or trips to the library, or family gatherings until he was almost 5. Now he's 7, and he can do anything he wants as long as he takes very frequent breaks. Instead of Ritalin, he has learned to self-evaluate regarding overstimulation, food issues, and needing to stay or go. I think this independence will benefit him for life. Also, he's two years 'ahead' academically.
4. I was a preschool teacher. I didn't want to hand my dc over to someone else, missing all the stuff that I think is really, really fun! 18 months to 5 years is a blast, IMO, and then we start the fun of homeschooling
So my dc are 9, 7, 5, and 18 months. They are all friendly and 'socialized' in the community. They know how to share...there are 4 of them! They know how to stand in line...learned it at the post office. They have plenty of arts and crafts, singalongs and music, play dates and field trips. They are also outdoors for hours and hours every day, instead of in a classroom for hours.
In our case, preschool and elementary school have zero appeal.