It depends on the intent of the test.  If the intent is to test the total time it takes for the promises to finish rejecting, then the test should report the time it takes for all the promises to finish rejecting.  However, if the intent is to test the machinery of *initiating* a rejection, then the test *should not* wait for the future tick rejections to finish.

The [original intent](https://github.com/cujojs/promise-perf-tests/blob/master/lib/tests/defer-reject.js#L6) of the test was *not to wait*.