I am going to make a bold statement: automated source code scanning as a primary application security strategy is dead. It just does not know it yet.
Before the vendor pitchfork mob assembles, let me explain.
The false promise
Source code scanning tools promise to find security vulnerabilities in your application before it ships. Run the code through the scanner, get a report, fix the findings, ship secure software. Simple.
Except the false positive rate is catastrophic. I have seen reports where 80% of findings were noise. Developers stop trusting the tool. They start ignoring findings. They treat the scan as a checkbox exercise. And the real vulnerabilities hide in the 20% of legitimate findings that nobody has time to review because they are buried in thousands of false positives.
What actually works
Manual code review by someone who understands both the language and the attack surface. Yes, it is more expensive. Yes, it is slower. Yes, it does not scale as easily. But it actually finds the vulnerabilities that matter.
Combine manual review with threat modeling, and you get a security assessment that tells you where the real risk is. No scanner can do threat modeling. No scanner understands business context. No scanner can tell you that the vulnerability in the admin panel is more critical than the one in the public FAQ page because the admin panel handles financial data.
The right role for scanning
I am not saying throw away your scanning tools. Use them as a first pass to identify the obvious issues quickly. But do not pretend they are a substitute for human expertise. They are a supplement, not a replacement.
Any vendor telling you their tool eliminates the need for manual review is lying to you. Buy them a drink, thank them for the entertaining demo, and hire a human.