@Signduck pay attention to this example.
There's an item with a capacity of 5. It gets overstocked to 7. There are none in the back. The "on floor" count is capped at 5 because of the capacity. Later on, 4 are sold. Then the "on floor" and on hand counts adjust automatically and instantly. Now, because of TMs overstocking and not changing capacities/quantities, the mydevice says there is 1 on the floor, none in the back, 3 total.
All you would have to do as a team member to prevent this scenario, is either A: adjust that quantity and capacity to 7 or B: don't overstock.