Because performance is unlikely to be repeated and at some point the person who is wrongly taking credit will not be able to perform, but this can take days or decades depending on the organization.
Decades? Are you kidding? Nobody's got time for that. Least of all people like myself who started in 2008 when the economy was utter garbage.
If you don't manage to build a decent career/salary/position by your mid-thirties in tech you're quite likely screwed (though before I'm too depressing, I understand there are counterexamples here on HN). Waiting a year or two for recognition is career suicide.
The point is it's highly variable. As stated in the first comment: whether it's worth the time and effort is up to you.
I'd argue that 1 year is way too short. The lack of patience causes far more problems today than building up the relationships and gaining the network and momentum to get into higher positions. Most people I know who stuck to a clear goal within a organization that has openings have done better than those who kept jumping around looking for the quick rise.