As someone who is second/third-tier on-call for most of the year: You know what's worse than getting paged when first-tier doesn't handle it? Not getting paged.

As someone who is second/third-tier on-call for most of the year: You know what's worse than getting paged when first-tier doesn't handle it? Not getting paged. The only person I ever had to formally reprimand for on-call policy wasn't the one who failed to answer on time, it was the person who, three times, acked and didn't say or do anything else only because they didn't know how to fix it. In all cases I ended up getting pinged by someone else (head of our support team, or a colleague working an odd schedule), after the situation significantly worsened. Higher tiers are there for a reason; don't feel bad if you've used them, only if you're expecting to use them. (On the other hand, feeling guilty for making a mistake is also human, and to some degree something that makes me want such a person on my on-call team. People who feel better when they do a better job will do a better job!)