Why is it unacceptable? The additional gap ("wiggle room") may be by design.Yes!! This is exactly what I am talking about! It wiggles if you swing the band left to right. Unacceptable!! It seems to be all watches not just mine!!
When materials heat up and cool down they expand and contract. Different materials expand and contract by different amounts. Suppose you had a tightly fitting metal bracelet in a ceramic watch and then left the whole thing in a hot car in the sun. You just might return later to find that the steel of the bracelet had expanded sufficiently to crack the ceramic watch?
Because remember, steel is a malleable material (it bends and flows when stressed) whereas ceramic is an extremely brittle material (it cracks). So, yeah, larger air gaps between dissimilar materials makes sense.