Need to especially check the cracks on the inner sidewall because that side is often overlooked/not seen. On top of that, the inner side never gets cleaned/oiled with tire cleaner so it tends to be more brittle. If we only check the outer side, often it looks not as bad and give misleading impression that the tire is still ok while in fact the inner side is already cracking. What happened to mine last time were mostly on the inner sidewall.