And of course you regularly check back for bugs and security issues, right?
In the context of web applications, frameworks mean that your devs don't have to be experts in SQL Injection, XSS, SSRF, Session management etc etc etc.
My experience over several hundred tests was that without a framework there weren't many apps that could get that right first time. If they were lucky the pentesters found the issues, if they were unlucky, it was attackers.