If a person is wealthy and doesn't need to spend that amount during the entire duration of Z, since they have other wealth to spend, they would likely choose Z for the higher return over the same time period.

So only a relative poverty would encourage the person to choose A.

Assuming they have unlimited life span. If not and their lifespan is uncertain, then the value of Z is reduced by the chance of not surviving long enough to profit from it.

If they can invest A and get a higher return than waiting for Z, then A is a more profitable choice.