- A tidy coffee machine. Coffee grounds are home for all kinds of living organisms that can make or break a cup of coffee. This is the killer factor.
- The water (hardiness, etc). Madrid has, arguably, one the best tap water in Spain and probably tops most European capitals. Most islands in the Mediterranean have sorry coffee due to the use of treated saltwater as tap water - from tap right into your espresso. Yuck! (obviously not a problem at a 5 star place where they use mineral water).
- The milk. For the best experience try the coffee in Galicia, and some parts of the North of Portugal. Some rural towns with a tradition in dairy production can give you a pleasant surprise if you're looking for that creamy taste with a foamy light texture. Rural areas is also where dirty machines dwell, so it's not a guaranteed good experience.
- The coffee and coffee culture. Generally most places carry the national/local brands. Italy definitely has the best mass produced coffee brands, but Portugal is a close second for their awesome ristrettos. The rest of cities or neighborhoods... It depends on how upscale they are. Ie. Chamberí is smart and upscale. I'm not comparing coffee shops with baristas, but the average coffee you get in the off-off places where tourists would not walk in but that account for 99% of all coffee served in Europe.
But I believe that's the least important factor tbh.
I admit I haven't been to Budapest or Bratislava but I've been to some of the supposedly-best places in Berlin and been pretty disappointed. A shocking fraction of them use UHT milk.
I drank a lot of coffee in Oz though. I loved how easy it is to get a good coffee. It seemed more accessible and standards higher across the board.
I personally really enjoyed Greek style Coffee but I guess not for everybody. I'm hardly what you would call a coffee snob here in Australia though.
From my direct experience European cities further East and North fare much better, I can say that with first-hand experience about the city I live in (Bucharest) and about Bratislava, too (which I've found to be better compared to Vienna). I've also heard/read very good things about Budapest and Berlin, and (as an exception to my first part of the post) I've found coffee shops in the Chamberí district of Madrid to be serving quite good coffee.
All this to say that the Italians do not have the monopoly on saying how one should drink his/her coffee or not, for the simple fact that the Italians mostly only care about a small sub-set of coffee culture (i.e. espressos/ristrettos)