Was it under a lot of snow from the driveway this winter? If it woke up three weeks later, I imagine it could have been. I wouldn't replace it since it looks healthy, and would see what it does next year.

Someone may have a more informed opinion, as I haven't seen that happen before.

If you did not see flower buds, they may have been eaten by pests (deer, etc) or killed if you pruned the shrub just as the invisible buds were being developed.

Just had thought.... I could not tell much from the leaves. However, I assume you have seen it bloom before and it is not a mislabeled hydrangea of another type that is not winter hardy in Z5, right?

Thanks ruth_mi and luis_pr. Unfortunately I haven't seen it bloom. I bought 5 incrediballs last year in late August for $5 each. All came in the same Proven Winner with the Incrediball tag stapled to it. It was cut back to an inch when I got it from the nursery so I didn't prune it this year. 4 out of 5 bloom beautifully this year. The leaves on the one that doesn't bloom look exactly the same as the other 4. I do believe my husband piled too much snow on it. I will cover it up this winter and see if it will bloom next year.

Incrediball's leaves look different underneath than Annabelle's and other hydrangeas. They have more substance, more prominent veins and a more silvery-whitish look to me.

Hopefully it will bloom great for you next year!