IAS 12 Initial recognition exception

hi,

what is the logic behind the IRE related to assets/liabilities not purchased through the business combination? for the goodwill it is clear that it is a vicious circle, as the calculation of goodwill will include the deferred tax effect.

is it the initial difference between the carrying amount and the tax base so that the principle that in the long run the temporary differences equate to zero does not hold for this type of transactions ant the IRE is the prevention to breaking the principle in this way?

thank you.