Why do you do what you do?

[Adonai One]

I'll just allow this to be a separate point and say:

(Service towards) Self = Nothing; As the concept alone denies all influence inpouring and outpouring, considering external influence of others nothing, not existing, not useful.

(Service towards) Other = Everything; As this concept accepts all influence inpouring and outpouring, all external influence useful and existing.

May it may be clearly denoted these both need each other for the SERVICE embodied in each to be performed. Your intuition can resolve the rest.