There are too many and they keep growing.
I read an article and it said there were about 250 ICOs so far in 2018, which could be estimated as more than 1 ICO came out a day
People keep talking about new ICOs everyday that I dont know they exist.
Also it is not anything rare that an ICO fails. Last year 2017 ~50% of ICOs failed. 50% is A LOT.