EXAMPLE: It has been a long time coming but the long wait has been worthwhile!
There is one particular use of the present prefect that is hard for some learners to grasp.
In "it [the present situation] has been a long time coming", the emphasis is on the idea of "to be a long time coming" at the moment when the speaker says that in the present time and not when this situation began specifically. The point is it began in at an undefined point in the past in relation to the present. Compare that to: It began a short time ago.
So, if you say: I've been playing tennis for five years", what matters is the five years in relation to today, the duration into the present. NOT WHEN the playing began. For that, we would say: I began playing five years ago.
The wait was long but the wait is over. As I speak now, it has just ended. What matters there is the ending of it in relation to the time of speaking.