probableprotogen , 5 hours ago

For the nazis, a big problem is the alt-right pipeline that plagues sites like Youtube, along with an unstable political climate, which generally causes radicalization (Weimer Germany is also a very good example of this phemona)

As for incels, a big problem is admittably a mental health crisis plauging many men, generally causing them to become resentful of women out of loneliness.

TLDR: Poor mental health and instability