As can be found in historical references of the period, the phrase ["high crimes and misdemeanors"] in its original meaning is interpreted as "for whatever reason whatsoever". This phrase covers all or any crime that abuses office. Benjamin Franklin asserted that the power of impeachment and removal was necessary for those times when the Executive "rendered himself obnoxious," and the Constitution should provide for the "regular punishment of the Executive when his conduct should deserve it, and for his honorable acquittal when he should be unjustly accused." James Madison said, "...impeachment... was indispensable" to defend the community against "the incapacity, negligence or perfidy of the chief Magistrate." With a single executive, Madison argued, unlike a legislature whose collective nature provided security, "loss of capacity or corruption was more within the compass of probable events, and either of them might be fatal to the Republic.

https://en.wikipedia.org/wiki/High_crimes_and_misdemeanors#United_States