Yeah I get what you're saying about the feeling of the possible guessing of the solution at the end of Poirot's stories, and I suppose that's something Christie noted as a lacking in detective stories, giving the reader at least some little possibility or sensation of possibility of reaching to the culprit.

That is one of the main reasons that the stories of Ellery Queen (at least some of them) were a kind of novelty for me. There you have the direct challenge from the author to analyze the problem and trying to reach the conclusions before telling you the solution