To be technical it reperesents taxes (for a DTL), that will be paid in the future, based upon different GAAP and Income Tax expensing conventions.
I remember it as follows, since less taxes are actually paid out under a higher expensing convention (for income tax) there is more taxes to be paid out in the future, all things equal. Think about a situation where there is only has one asset owned by a company worth $1000. If the company depreciates it as $500 the first yr., $300 the second and $200 the third for income tax purposes, while for GAAP acocunting purposes depreciates it straightline over 5 yeras you will actually have a significant DTL over every year until the asset is fully depreciated to zero.
Basically the tax savings in years 1-2 will rear it's ugly little head in year 4 and 5, hence the decrease the DTL in those years (4&5) and the need for one to begin and end with.