The #1 problem I see with resumes is that people tend to write about responsibilities instead of accomplishments. For example, I’ll see:
Ran security scans against application code to find vulnerabilities
Wrote reports on vulnerabilities found and presented to engineering leadership
The problem with that is, as a hiring manager, it doesn’t really tell me anything interesting. I don’t really care that you ran security scans against code to find vulnerabilities. Ask yourself why the person reading your resume would care about what you’re writing. Oh wait, you “Ran security scans against application code which helped reduce critical and high vulnerabilities by 70% over a period of 3 months” – now that’s impressive and that’s exactly what my team needs! Bring this person in for an interview so I can ask them more questions about how they accomplished that!