Does anyone find anything wrong with companies that have very high margins?

June 21, 2023
by a searcher from Boston College in Pittsburgh, PA, USA
Obviously, intuitively the higher the EBITDA margin the better, but has anyone had experiences where a higher margin meant something not as desirable behind the scenes? In the sense that the margin is "too good to be true", perhaps there is customer concentration, lack of regulation, they misrepresent the numbers, other things I am missing?
from Stanford University in Dallas, TX, USA
from York University in Waterloo, ON, Canada