Every action has a reaction. This is the law of karma. Good karma is referred to actions that occur according to the 4 vedic values of the vedic philosophy:
Satya - Truth, always tell the truth
Saucha - Cleanliness, purity
Ahimsa - No violence
Tapas - austerities
In contrast bad karma are actions that are performed without respecting these principles.
""Person 1 helps out Person 2 on the premise that this deed will accrue "good karma"."
Let's pause right there. Person 1 is helping Person 2 for accruing Good Karma! Then obviously the intent of the help is "not to help but accrue good karma" and yes that's obviously bad. The intent must only be to help for the sake of ...
Yes, It means you are in Moha, you should not love or hate anything and should be neutral with everything.
I can give you many examples how can it be a moha, for example, if you love maths or CS that means you are able to solve the problems easily or you are learning something new every time, But this will create a false ego and feeling of superiority or ...