These developers don't just retire. They come back under different aliases.
Just like shampoo. Apply, rinse, repeat.
They just keep building more scams, more flashy wallets and flashy websites, and keep suckering people as long as they let themselves be suckered. Each scam is slightly different.
What's laughable is 11 days after the crowdsale / ICO was concluded, a user Rw13enlib88 asked this simple, but important question AFTER the money was already raised:
@Viorcoin are you doing all the work (coding/marketing/exchange contact/etc) by your own or you are part of a team? (just checking before investing...)
To which the developer beat around the bush and said:
NO/YES
...I mean people were so excited to invest early, they lost their minds!