Or a lack of understanding for what?
For pushing a head into the sand and pretending that our style is a GOAT style and that we are losing in the same manner for 30 years: because of a bad luck, individual mistakes and because of a random scapegoats?
Lack of understanding of all, mainly visual, aspects of the game, which cannot be expressed by numbers.
Although 'game-systems' can be expressed by numeric or math expressions and equations and can be modeled (to a certain extent), the most frequently quoted numbers in football do not necessarily represent the factors which are quality related.
Mere results, trophies won, the number of shots, etc., can certainly be guiding factors but rarely tell more than that.
The 'HOW' a result has been achieved factor is the one that usually can only be expressed by longer descriptions, mere data doesn't represent the actual game.
Just like the last Barca game, where the opponent had 3 shots on goal and won by 3:1.
Unless watching it again and again, even goals tell nothing more than just what they were, because there are lucky goals, easy goals, dirty goals, own-goals, etc.
If your opponent's defender gives away the ball to your attacker and he scores, no statistics will ever reflect upon the fact if it was a goal scored due to a huge MISTAKE by the opponent, or if it was the result of a beautiful attacking combination.
The numbers don't speak about the 'how' and the 'why' factors.
What about recognizing patterns on places where others don't see them?
Someone will recognize patterns and deeper problems.
For the mentioned patent recognition you need data, that is not really available in football.
If your team lost twice as many times with X as the coach, compared to Y, yes you can see a pattern, but it only tells you the given variable's value for the coach. It can not express stylistic values.
This is a very ancient question, namely if a team is successful BECAUSE of they play nicely, OR they were successful due to other factors or circumstances.
This is a typical "Which came first, the chicken or the egg?" question.
The numbers can NOT tell you about the quality. They state the result. The end-result only.