Do you know if the current vaccine schedule is based more off of that specific schedule being the most optimal time to get each individual vaccine or the fact that people are much more likely to actually get them if they're done all at once very early on?

ie. is it possible that the current vaccine schedule is more for assuring the likelihood of more children getting them all rather than it being the most optimal time to give them for greatest efficiency against disease?

I couldnt find any reliable info after a couple of searches.