i think it also a matter of focus , most people focus on the now .. at best today or a week hence , and by doing so we tend to assume things will not change ... we plan to buy milk on the way home from work , or we plan for go to see a film at the week end , all things / events become static in the now , even when the " now" is tomorrow, none of use plan for 5 generation hence ..( ok may be we should be re green house issues ) we tend not to see things in long time span , and we do not see changes effecting use .
so we see your actions/events as objects .. and we speak in fixed time .. a fist is a fist (object) not a transient formation of fingers and palm (event) even in the passed and future we still view it fixed at a static time .. only in writing style might someone say .. "and my fingers came together to unite with my palm to form that construction called a fist" ..
our perception is time locked by the fact we cannot move backwards or forwards in time .. its is always now , so the chain of events that is appleing , or peopleing or abiogenesising are not see .. we only see what is in frount of use .. the rest of the chain is disconnected someware else .. in a place we cannot visit .