Guillermo Flor Guillermo is a Spanish angel investor, writer and Entrepreneur magazine columnist focused on AI startups. He started as a corporate/M & A lawyer — PwC (2017–18), then Garrigues (2018–19), advising PE funds on $30M+ M & A and LBO deals — before co-founding Tueri, a B2B SaaS contract-management startup, as CEO (2020–22). He raised six figures in VC, failed to reach product-market fit, and shut it down: the origin of his PMF obsession.