Every explanation is in fact a narrative, a story, a myth. A perspective through which whatever agreed-upon facts of the story can be viewed.
Any perspective could be valid; each suggestion for the subject discussed is possibly a good one. By asserting the ‘root cause’ of a phenomenon, you are implicitly claiming “the way things work”. This reflects, in essence, how you think the world functions. It is your ‘religion’, your world-view.
When you describe why or how something happens or is, you are describing in a sense how you believe the world works. Now, you could be right… and you could be wrong. Any scenario can be described in different ways, all equally “correct”. Whatever reasons come up in your mind are not necessarily the best explanation, they’re just the way you happened to think about it.
Some theories might have more explanatory power than others, but your very ability to assess the true explanatory power of a theory is exactly the thing you cannot be certain of: you just don’t know how much you don’t know, because that is how not knowing things works.
All that we can be sure of, is that there’s nothing we can be sure of.