Why do the front wheel bearings keep going bad?

5/18/2011 both done at Firestone
07/31/2013 both done again at Firestone
7/15/2016 Left done only
Now I have been told the right needs to be done again
11/24/2016

The life of a bearing is often a function of the preload. If they are not torquing the axle nut to the proper number of lb.-ft., it can greatly shorten the wheel bearing's life. They may be using an impact wrench, instead of a torque wrench.

Quality wheel bearings should last at least 100,000 miles, if properly installed.

I have rarely ever had to replace bearings. Sounds like they were tightened too much to start as TX notes.

Unless you work for a courier service and drive 60K+ miles a year... I'd stop going to that Firestone. Just because someone knows which end of a screwdriver to use... doesn't make them qualified to be a mechanic. And I've seen WAY too many of these people working as one.

My 2 cents worth....idiot "Mechanic" got dirt in the grease while packing then, and/or improperly torqued them. Assuming these aren't sealed bearings then its likely over or undertightened

Maybe someone other than the Firestone you have been going to should do this job.