Only possible if you don't do anything novel. If you are building a website that's got all the same patterns as the previous 5 websites you've built, then you c

Only possible if you don't do anything novel. If you are building a website that's got all the same patterns as the previous 5 websites you've built, then you can provide a solid estimate and deliver on time. If you're building something that nobody has ever made before, you've got unknown unknowns, and your best bet is intuition, which is inevitably going to miss the mark a bit.