everyone thinks of themselves as a "good person", then proceeds to do whatever it was they were going to do anyway.

Living implies in response to procession...good or bad implies a conflicting response within a conflict of reason (good vs bad). Being (life) processed from inception towards death is neither good or bad...

doing a good deed for the right reasons

Reason implies good vs bad + right vs wrong...a conflict; no matter which side one chooses. A deed/action implies being (life) done (inception towards death) by, hence reacting to.

Reason implies reaction vs reaction, while both sides ignore being enacted upon.

Really thinking this through, though, "being a good person"

How could this thought go through if one holds onto being good? Meanwhile...person aka per sons (by sound) implies sound going through each instrument (structured mind within).

Not many people are ready for that.

a) Does each one wield free will of choice to react to all perceivable? Could it be that others suggest nihilism (not); collectivism (many) and pluralism (people) to distract one from discerning self?

b) What if ready implies RE (reaction) DO (action)? What if being implies reaction (life) within action (inception towards death)?

It's painful to have to watch

How are you watching? Perception (sight) or suggestion (focus)?

FO'CUS, noun - "In optics, a point in which any number of rays of light meet, after being reflected or refracted"

What if point of death is painful to life sentence? What if ones perception gets harmed by focusing on suggestions by another? What if sight narrows by focus? What if focus during motion heats up matter?

If pain (inception towards death) then gain (life)...