Multiverse Standard Time (MVST)

The rigid and unyielding laws of Multiverse Standard Time (MVST) maintain that time flows in one direction only across all of the universes in the Multiverse at a constant rate. The laws of time in each separate universe may have different flow rates, times, and abilities to loop back upon themselves, but time across the entire Multiverse flows at a fixed rate and touches all universes.
This is the reason why there are no real Time Lords and these are just the fictions of too many imaginations of too many beings across the universes.