What is the significance of tire minimum pressure? Its quite intuitive that tires have maximum pressure figure - inflate it more and something could explode. Furthermore, it is common knowledge that under-inflated tires result in snake bites. What puzzles me is that all tires indicate minimum pressure. This could be somewhat justified about DH tires, which tend to be produced with thick sidewalls and thick soft thread pattern, resulting in reduced pinch flats (among other advantages). However, on different cross-country tires I have seen minimum pressures from below 2bar to 2.7bar at least. Is this just marketing or does the number mean anything? Furthermore, how can the manufacturer know what the riding terrain and rider's style is? In my opinion those affect chosen tire pressure a lot more than sidewall thickness.

Even if the bead remains seated and no pinch-flats are suffered, an underinflated tyre will over-stress its sidewalls whenever there is a torque difference between the bead and the contact patch.

This problem would be visible as rippling in the sidewall.

This stress results in the carcass grain becoming visible through the sidewall rubber over time.

Many fatbike tyres, designed to be used below 10psi, will develop visible carcass grain over the life of the tyre. I would not expect a standard MTB tyre to experience sidewall rippling at all if maintained above a minimum pressure appropriate for the load (i.e. a higher minimum pressure for heavier, faster or rougher riders).