According to the original notes of Moussorgsky this piece ought to end with ff without diminuendo. Probably with the image of a cow cart leaving far, the piece ends in pp with diminuendo in the music notes published by Stasov according to the interpretation of Rimsky-Korsakov (as is in the orchestration by Ravel).
But no work dealing with a cart or a cow was found after all. On the original notes of Moussorgsky there is a trace of rewritten title after deleting the first title by a knife. When Stasov asked Moussorgsky about the meaning, he ought to answer, "among us let it mean a cow cart". Namely it is interpreted, "It is not a cow cart but truly the Polish people suffering from Tyranny. Leave the meaning as a cow cart in public." So it is easy to speculate that Stasov knew the truth and wrote "A Polish load cart with big wheels drawn by a cow" on purpose, paying political attention.
From this stand point of view we can infer that the found sketch entitled "Rebellion in Poland" should have given the concept of the music to Moussorgsky. If it were so, the anger of fortessiomo to the last might be adequate for this unmerciful guillotine.