Why do startups raise investment capital using SAFEs?

SAFEs solve a number of issues that convertible notes have for startup companies. Because SAFEs are not debt instruments, they remove the threat of insolvency that a convertible note can cause and they remove the need for founders to go back to investors to request maturity date extensions (this also saves investors from having to deal with extension paperwork). Additionally SAFEs reduce the amount of legal cost and negotiation time by simplifying the agreement relative to most convertible notes.