The simple answer is: You must use economics to answer this or any other general question of product quality as it relates to maintenance that is not totally crystal clear. Here you would find the minima of the sum of the costs of changing a roller, which you know all too well, plus the costs of NOT changing a roller, which you likely do not know as well.
The costs of NOT changing a roll are the incremental increases in waste, delay and customer complaint with regard to trying to squeeze more running time before taking the machine down for repairs. Since you know the costs of changing well and the costs of NOT changing NOT very well, you will, as a rule, run too long or way too long and cost your company needlessly in extra waste, delay and customer complaint.
Bottom line: Know your defects and know economics and do the work to best serve the bottom line.