Pallet switching can be necessary for many reasons.
It is perfectly possible that you need a different type of pallet.
In a number of sectors, it is standard for goods to arrive on a wooden pallet.
For hygienic reasons, however, they have to transfer these goods to plastic pallets.
It also happens, of course, that you have damage to a pallet or to the load underneath.
To replace it, you then have to stack over it.