People are hard to coerce by force alone.
“why do these fellows feel like they must or ought to serve. A lot of historical fiction or fantasy settings fail to address this particular question or else answer it with a very crude ‘because they have to’ (that is, compulsion) but that’s not usually how this works. After all, this society is about to give these fellows weapons, so without some broader social structure that encourages or constrains them to remind at the standard, there is very little preventing them from deserting or revolting. Compulsion can get me into the ranks, but it struggles to keep them there.”
https://acoup.blog/2026/06/05/collections-pre-modern-armies-for-worldbuilders-part-i-why-they-fight/