Application Monitoring Is The New Unit Testing
instrumentalapp.com
instrumentalapp.com
Waiting 'til you ship to production to find a bug is a really, really, really bad idea no matter how fast you diagnose it. If your site is doing any serious scale, this could cost a year's worth of dev salary in the time it takes to make the fix.
Application monitoring is a useful tool, but the implications of overselling it will lead to some real problems for teams that aren't wise enough to see the forest for the trees.