Folks that do their own bike maintenance should know that adjusting the cone & cup axle needs to compensate for the compression of the QR skewer on the bearing adjustment. In other words, there needs to be a small amount of play in the axle when the skewer is loose that gets taken up when the QR skewer is tightened. Failing to compensate can put excessive preload on the bearings, displacing the grease, leading to rapid wear and pitting.
A wheel-on trainer that holds the bike in place by clamping to the axle/QR skewer can add additional compression force over and above what the skewer alone does which can negatively impact the bearing adjustment leading to premature wear. Having worked in a bike shop as a mechanic for years, I should have known better.
