What does the poem mean by "elbows turned out"?

Poetry without the meaning of "elbows turned out"

First, turn your elbows out. Meaning:

1, people's arms are all inward and backward, which means selfish.

2. The commendatory meaning of "eversion" is selflessness; The derogatory meaning is "unselfishness" that is inhuman and can't tell right from wrong.

For example, I did something that hurt my relatives and friends or the department where I work.

Second, similar idioms include: eating inside and picking outside,

1, eating inside and picking outside [ch and lǐ pá wà i]

(1), explanation

Accept the benefits of this, but work hard for that. This also means telling each other about your situation.

(2) Making sentences

The accountant in this factory ate inside and picked outside, and as a result, he was expelled from public office.