1/ If you’re a founder you’ve probably heard someone say “oh, I’ve seen this idea before - it didn’t work” or “isn’t this just like that other thing that person/company X tried?”
2/ As a founder, I heard this dozens of times. It’s likely to come from investors, but you hear it from other founders, potential employees, advisors, customers, even family members. Like it or not, pattern matching is strong.
3/ I get contacted from a new company every 3 months working on a idea that's similar to Frank (our old startup). And our idea was similar the original Lending Club and Prosper idea - but with a unique twist, of course :)