Do You Buy Early Access Games?

I am with the normally wait 1 year after release camp!

I'm just to picky about games and want final reviews and a few patches before I play a game. Plus I am so far behind on interesting games that there's just no point in me paying full price for a new game right now.

Provided it looks interesting and possible I'll buy them without hesitation. That being said I don't usually dump more than a few hours into it that early.Enough to get a feel for it, but not enough to burn out on an unfinished product.

I've bought 4 early access games. Two (Eisenwald and Grim Dawn) because I missed the kickstarters and would have backed them. One (Might and Magic X) because I wanted to show Ubisoft that there was still a market for Might and Magic games and one (Bloodlust Shadowhunter) because the steam reviews convinced me it was a project that was worth supporting for me. I will never play Early access/Beta games. I want to enjoy the finished project, and I think I'd ruin this for myself if I played the beta. That said, cheers to all you beta testers. You help make games better.

While I am buying lots of games on KS to support the developers I hardly buy them on steam Early access.

The reason is just that the deal isn't as good as the deal they offer on KS. I don't play Early Access Versions anyways, so in most cases the only thing mattering to me is "what advantage do I get?" and in most cases it's just better to wait. Even Early Access games often get into sales. So you can get a game in a sale even before it releases.
And that even Early Access games can fail can be seen at the game Spacebase DF-9

BTW: There is a podcast about this topic on three moves ahead.
The panelists are
Rob Zacny (Writer and Moderator of this podcast)
Tyler Sigman (Darkest Dungeon)
Jon Shafer (Lead Designer on Civ 5, now working on "At the Gates" with his own company)
Soren Johnson (Lead Designer on Civ 4, now working on " Offworld Trading Company" with his own company)

https://www.idlethumbs.net/3ma/episodes/early-access-1

No. I'm the skeptical type, and want my game to be complete. So I only buy after all patches, DLCs etc. are done. Typically GOTY editions. As compensation, I do buy games that I don't play for long, to reward the developers for making them

Of course.