the ndp are stepping away from the liberals and they are pointing to stalled legislation, which ought to be a good reason, but the reality is that ther polling is cratering, as they're seen as being a part of an unpopular government.

this is tricky in a three party system.

generally, a decrease in ndp support most benefits the liberals, and if you're familiar with thinking in the ndp, you might realize that a primary purpose of the coalition agreement was to prevent an election the conservatives would win.

had trudeau just fucked off years ago, the liberals might be in a better position. currently, there's no foreseeable outcome but another liberal minority, and a decrease in ndp support would indicate that they should call the election now and not wait. 

the actual reality is that the leadership of the ndp would approve of that.