A farmer knows the answer to this question very well.
See, what does a farmer do? He takes the seeds, ploughs the field and then throws the seeds. Some seeds sprout and some don’t. He does not worry and think,’ Oh, this seed has not sprouted, that has sprouted.’
He just puts the seed and whichever sprouts, sprouts, and whichever doesn’t, it doesn’t! Usually most of the seeds sprout if it has been ploughed properly. And if the farmer has sown the seed at the right time, it does grow.
That is what we should all do. Don’t worry about how many will reach the goal and how many will not. You do your job.
A musician simply sings, he doesn’t see how many people are listening. If someone is playing the flute or the sitar, there is no guarantee that everybody sitting in the audience are keenly listening to the music. Some may even doze off while the music is playing. That is their prerogative