Ya never know. If the seal goes bad, all the grime that gets in there will eat the bearing up. Add in a little time and rust and before you know it, youre doing the bearings.
The previous owner could have hit a few major potholes somewhere along the way also, as to speed up the bearing aging process.
I would pull the hub off to take a look. You'll have to take the caliper off and hang it on the side with no load on the brake hose. Clean it up spindle/hub/bearings, repack it with fresh grease, and set the pre-load on the hub nut. (no load-no play).
'84 190E 2.3
'83 Porsche 944 (track car)
'84 Porsche 944 (parts car)
85.5 Porsche 944 (sled)