What happens when not many people take an interest in this NFT and only a few are sold? What then? You're not gonna push and complete the entire roadmap?
Will those who purchase the NFT be reimbursed if that happens? This is the first time I've seen such a roadmap on an NFT or even a crypto-project.
You claim that it's the first time you've seen such a roadmap ... sorry but this shows that you don't know NFT projects very well ... I'll just give you a couple of names but if you want I can send you a long list!
https://breed.thekittybutts.com/#roadmap
https://boredapeyachtclub.com/#/home#roadmap