Q. I have seen often people striking the ground with the arovos on Hoshana Rabba until most or all the leafs are gone, and creating a great mess in the shul or at home is that correct.

A. Mishna Berura (664: 19) quotes Arizal that one should strike the hoshanos five times on the ground followed by hitting on utensils to remove some of the leafs; not all leafs need to be removed.
Bikurei Yaakov asserts that one should hit the arava with might and indeed remove leaffs as this is a symbol to the end of the severity of the days of din and judgment.
However, Chaye Adam (153: 3) mentions that the removal of all leafs is customary by children complying with the mitzva. Mekor Chaim claims it is the minhag of the uneducated and boors.
Piskei Teshuvos (ibid. 5) further explains that the opinion of the Arizal is that none of the leafs should be removed, on the contrary, the aravos should be maintained as kosher as the ones on the lulav, with their leafs on. He adds that according to the Arizal the hoshanos should only be struck on the ground five times. The above is echoed by Kaf Hachaim (ibid. 37), Pri Megodim, Kitzur Shulchan Aruch (138: 3) and others.
Horav Shlomo Miller’s Shlit’a opinion is that one should follow the minhogim of his family and congregation. However, the Rov advises to collect all leafs, if any were left on the ground and not to step on themas it constitutes bizui or desecration of a mitzva. (See Shharei Tzion ibid. 2).

Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit’a