interesting question..they do not make a 8.3 or 9.3 amp fuse,for example so if the designer calculates that the intended circuit could be 8A+ then a 10A would be specified.but if there is no problem in the cicuit then the 8A will be fine.if it were me i would but 5 each of every value of fuse incase another problem exists or eventuates fron time.
