~Snip
If we talk about the perfect club we will never find one like that, maybe they never lose but they still draw. So far I've noted Leverkusen who can do that but they also still draw, yes even though they never lose. In football a draw will still count as an unsatisfactory result.
All with their own advantages and disadvantages, every time 2 clubs meet, they will always look for gaps where their opponent's weaknesses lie and if they can be utilized properly they will be able to win the match.
But other factors also sometimes affect the outcome of matches, one prominent example is luck. No matter how strong and how many chances a club can create, they won't be able to score if they are unlucky in the match.
I really agree with your last point, without luck a team may not win the match. Luck is part of the game, but good performance and creating a lot of chances allows a team to increase its chances of winning a match. In the Champions League, there are only 3 teams this season that have never dropped points until they qualify for the round of 16. Bayern Munich, Real Madrid and Manchester City are the 3 teams I mean, in fact I am sure they will maintain that record to qualify for the quarter-finals.
In the round of 16, we will probably easily determine favorites in many matches. Bayern Munich, Real Madrid and Manchester City are favorites in their respective matches, while Arsenal, Inter and Barcelona are also worthy favorites. PSG and Dortmund are also favorites, but I tend to think that the first 3 teams I mentioned have a good chance of securing a ticket to the quarter-finals.