FWIW, the most common problem (based on threads here on ES) with integrated-BMS ebike packs where the BMS has caused the pack failure is that the cheapest possible BMSs are used, not only in manufacturing, but also in design. So there are no safeguards against certain kinds of cell / wiring failures (the BMS simply can't tell something is wrong), and no protection against failed BMS components damaging cells thru group discharge via balancers stuck on / etc., or thru letting the cells overcharge or overdischarge.
If good-quality, well-designed BMSs were always used, it would be much less of a problem. (though since many of the packs using cheap BMSs also use cheap cells (sometimes even recycled garbage), the pack would still fail--just not because of the BMS).
If good-quality, well-designed BMSs were always used, it would be much less of a problem. (though since many of the packs using cheap BMSs also use cheap cells (sometimes even recycled garbage), the pack would still fail--just not because of the BMS).