As you say, there is no algorithm. It is largely a judgement call, made individually and then collectively by a group of people. But they will look at a lot of things, not just your publication record. Don't neglect that.
The "standards" will be different for a post-doc and for a regular position. A post-doc will only be around, perhaps, for a couple of years but a regular faculty member likely much longer. So for a post-doc the actual research activity and potential isn't balanced by other considerations and becomes more important (paradoxically, perhaps). Some post-docs are later awarded regular positions, but that is because people have had a longer and better chance to evaluate you.
But if you are in the running for a regular position the evaluators will want to know a number of other things about you, beyond your research and research potential. What is your fitness/match for the particular position. How will you "fit" into the department? Can you be a future collaborator? Are you too arrogant? Too humble? Can you teach? Can you advise students? Do you seem to have more ideas than one person could reasonably develop themselves? Lots of things, depending on the position.
I've seen one case of a brilliant researcher not get a bid because she just wouldn't fit into the department or be accessible to its students. She was judged too good for us, even though it was a (very) top US program.
On the other hand, another person got a bid, precisely because it was felt she would be a good collaborator for one of the junior faculty, enhancing both people as well as the department.
Don't ignore your research and publication venues, of course, but be aware that you need more and should do some things to develop in multiple dimensions.
