Leaves foreign articles and fails financially (4,5)

'leaves' is the definition.
The definition and answer can be both to do with motion as well as being verbs in their -s form.
Perhaps there's an association between them I don't understand?

'foreign articles and fails financially' is the wordplay.
'foreign articles' becomes 'under'.
'and' means one lot of letters go next to another.
'fails financially' becomes 'goes' ('go' can be a synonym of 'fail'. I am not sure about the 'financially' bit.).
'under' put after 'goes' is 'GOES UNDER'.

Can you help me to learn more?