Things aren't really caused in a linear cause-effect kind of way. It might sometimes appear or work like that. But generally speaking there will always be multiple, simultaneous causes. Everything is interconnected. It is not even very correct to say that anything causes anything else.
Stuff happens because it is part of the reality of what is happening.
Any event is its own cause, for that matter. Cause and effect are simultaneous. Each technique is built on a different model. If the technique works, all it means is that the technique worked. It doesn't mean that the model is now the exact, precise reason for the previously observed phenomenon.