When a process terminates in a dirty way (e.g. a visual studio software killed by "stop debugging", dbMonitor keeps the process in the process list. It's possible to clear the log, but the process remains and cannot be removed.
This sounds useful as a default for "remove process", as usually a process that is still running may still be or become of interest again, but for processes that doesnt' exist any more it would reduce the necessity to restart dbMonitor every few hours.

Maybe (although clearing the log should help even more), this would even support https://devart.uservoice.com/forums/38671-entity-developer/suggestions/12519276-fix-out-of-memory-exception-in-long-running-dbmoni and it may be related to https://devart.uservoice.com/forums/104635-delphi-data-access-components/suggestions/4364547-clear-all-terminated-processes-button-for-dbmonito