This seems like it would be subjective but it actually tells a story. Most likely tickets aren't being broken down enough, one employee could be snagging easy bug tickets in the morning and another employee could be working on a epic feature.
On the other side of things I have a guy at work who rocks out 20 tickets and a guy at work who tries to go into super plan mode and take his time and make sure every semicolon is perfect 20 times. This is ok, it's what management is for I need to make sure the fast guy is a little more careful sometimes and I need to check on mr planner and make sure he speeds it up sometimes.
One time I got laid off for not closing enough stories. Meanwhile the guy that was kept on was the source of a lot of bugs. So what is that if you generate your own problems and "solve" them?
That's a different problem from the one Planning Poker addresses.
But to answer your question, the original story should have acceptance criteria such that the ticket can't be closed if there are bugs. Failing that, the bug ticket should be linked to the original ticket.
Continual feedback is also important. If the manager who laid you off valued velocity over bug-free code, that should have been communicated way earlier.
Alice works with both of them, and knows that the one ticket Dave is working on requires a lot of refactoring work to solve it nicely.
Or knows that Bob is just that good. Or Dave's having a bad week because of X.
Direct superiors tend to have at least a vague idea of what is happening, along with a certain level of trust. These two make it less likely for the answer to your question to be as ambiguous. At least for ballpark estimates of whether one should be worried.
Metrics should always be supplemented with communication. If Dave's performance is under question, talk to him and find out his progress on the one ticket he's been working on.
EDIT: realized after posting that multiple people made this point. Just goes to show that it should be common sense.
On the other side of things I have a guy at work who rocks out 20 tickets and a guy at work who tries to go into super plan mode and take his time and make sure every semicolon is perfect 20 times. This is ok, it's what management is for I need to make sure the fast guy is a little more careful sometimes and I need to check on mr planner and make sure he speeds it up sometimes.