I always do the checklist for Kickstarters:
1. Does it really need my help before the campaign is over?
This mainly is checking to see if my contribution really helps push a stretch goal, or just get it funded. This disqualified some games like Mighty no 9 (good thing), Bloodstained, Shen Mue 3, etc..
2. Is there something KS exclusive that I can't get afterwards?
This has to do with exclusive promos, hard copies, etc.. I usually don't care too much so this doesn't sway me much.
3. Will it be available after the KS?
Somethings are hard to predict, such as the Glory for Rome Black Box, but most things can be retrieved afterwards. Promos and physical goodies may be harder to get.
So pretty much I only back visual novels I feel wont make it (which most do) and I've been Kickstarter free since the end of Muvluv, which I regret a bit honestly, since I could have received the physical Vita version anyway from retail stores.