Ok help me out here i made a batch of Jello pudding with powder milk and i notice it was not as good as it would have been with regular milk

i stirred it like i was told to and it come out ok but it took longer to set up in the fridge than the one with normal milk .i let the powder milk get cold overnight and used the milk as it was need in the mixing directions as on the box .

So anyhelp here on the way it turned out the way it did