Absolutely. There are some appallingly poor strikes - for example many of the WW1 George V pennies. An UNC example, can still justly be referred to as UNC, or "practically as struck". But in such cases an EF (or even GVF) coin with a good strike (ie complete breast plate and decent hair detail), is going to be far more desirable  than an UNC coin with 100% lustre, but no sign of a breastplate, and a slaphead King (for want of a better expression).