How to reduce the number of missed defects during regression?

Question

Software testing

Once a quarter we submit the release for acceptance tests, each time with a bang. The regression passes, we update the checklist every time, to no avail .. Actually, there is one big checklist for the entire program, we go through it once per regression.
How can the regression process be improved?

Answer 1

1) For each regression bug, analyze the reason why it was missed: (a specific case was not covered by tests, a functional section was not covered by tests, it was not tested for a bug, etc.).
2) Write a high-quality exhaustive set of regression test cases. First of all, according to the results of the work from paragraph 1
3) Automate everything that can be automated.