It takes months and tens of thousands of dollars to build a recognizable brand - and even that does not guarantee success
Why not ? If the project is interesting, it'll most likely succeed. I didn't see a (legit) project yet which ran its camp. for a long time and not succeeded. Can you name any? I think most of them just couldn't make it long enough due to low cash in hand.
There are no guarantees. Projects fail not only due to low cash in hand, but also due to various other factors such as poor execution or a lack of demand for the product or service. Numerous projects have run signature campaigns for months on end but ultimately failed to make a significant impact on the community. Consequently, these projects gave up and eventually faded into obscurity.
Just a few examples that I remember from my time here:
MyCryptoMixer.com ran a campaign for 40+ weeks but ultimately failed due to unknown reasons.
Bitamp Web Wallet ran a campaign for 28 weeks during 2020/21. The project is practically dead now as far as I can see.
Go-Overt ran a campaign for 16 weeks but failed.
YOLOdice casino campaigned for over two years but ultimately closed its doors.