Source: Curse

Have had an issue today where any kill is adding an attempt to the last mount I tried to get.
I.e. Killed Ruhkmar, 80 attempts. Kept playing and every mob kill has added an attempt to Solar Spirehawk, now at 186 attempts. I have found that if I reload my UI after each boss kill it stops any further "attempts" tracking.

to answer your question it is happening with any boss that drops a mount. Lately I have been running Helfire Citadel, Freehold, Kings Rest and Mechagon, after every boss kill the count goes up for whatever the last mount attempt was.
Eg. I run Freehold, kill the last boss only, count for Sharkbait goes up by 1, then I head to Mechagon and because I have to kill 3 bosses to trigger the Aerial Unit the count for Sharkbait goes up by a further 3, then when I kill the Aerial Unit the count for the Mechagon Peacekeeper goes up by 1. etc.

Not sure what to make of it. At first I thought maybe there's an issue with combat log events, but some of those user another method.

Worth investigating if there's some connection to #742?

I didn't encounter any such issue in my testing, so the best guess I can offer is that some other addon might be interfering.

For now, I'll close this since I can't reproduce the problem.