It is normal to see some track marks....but it should not be cutting into very far. How deep are the cuts, or is it just more like scratches on the top? My mats will break on the lines made especially my long strip boards. But it does take a while but I can start to see the lines shortly after I start using them. The scratch lines don't matter unless they get deep enough that they start not cutting in places although I sometimes need to clip a thread or 2. When they get used enough, they will actually "crack" and you will not be able to cut with them. When the mats are used enough that they are leaving a thread or two to cut or look like the groove is getting deeper, I will go ahead a order a replacement mat. I like to have pre-ordered replacement mats to have on hand for my most used dies..but don't get too many as the mats can "age" and get brittle too...that however would probably be years rather than months.