[Suhiir]

Really depends how your tank-infantry teams are trained to operate together.

For the most part the US Army was (is still?) equipped/trained for "The Big Battle", a primarily armor vs armor engagement. In such a case the infantry supports the armor who sometimes seems to forget infantry can't move as fast when dismounted and doesn't have 4+ inches of protection vs small arms/artillery. Additionally the armor-infantry ratio means there just plain aren't that many infantry to work with each tank.

Us Jarheads (USMC) view tanks as an infantry support asset, and don't have near as many to start with. So the ratio of infantry to armor is much higher and the armor tends to "hang back" with, and often behind, the infantry screen until called forward to deal with something.

The environment your trained to operate in and basic mindset (infantry supports armor or armor supports infantry) is important.

Then you have a lot of military forces that really don't train much in combined arms so have significant difficulties in the first place.