This is a somewhat general question by design, intended for discussion of process. At my current (and all previous) companies we had issues with releasing insecure software into production. This cut across the divide from mobile, web, API's, internal, external, critical and non-critical applications and systems. If we built it, it had/has security issues... just like your company. In addition, we lack support stack (qualified application security engineers who "knew code" and not just glorified pen testers who didn't know JavaScript from Java) so we could not scale services as needed. Hence automated software security scanning in the SDLC and now in the DevSecOps CI/CD pipelines. We face the issues of:
Service Level Agreements - our dev teams want/need results in minimal time, we all know that's not happening with either DAST or SAST tools without heavy configuration.
Allowing teams to choose their own language and not even having static code support... leaving us with DAST if applicable or, ugh, pen tests, which in my view are essentially useless.
We need to shift software security "left" - from point of inception, not wait until code is in production and hope we detect the vulnerabilities - I am sure someone will find them, most likely not the pen test team we are paying huge money for, however.
Automation of static and dynamic tools, properly configured, driven off a threat model seem to be our only options to get ahead of the game. We all know "developer education" is a lost cause.
How is your company/team solving this, assuming they even are or recognize it as a problem to address?