Xt Shifters and cable housing question

I'm in the process of building a new bike. I'm installing new xt shifters and was wondering if the cable housing is supposed to fit snug inside the barrel adjuster. I do have an end cap on the housing but it still slips out of the barrel. My other bike has Deore shifters and the same housing but seems to fit snug inside the barrel. What am I missing?

Thanks in advance.

 

I believe its just tension that holds it in place. When the cables are pulled tighter, there isn't any space left to slide out of the barrel. Pull with your fingers to create tension and you will see it will fit snug.

 

Ah...makes complete sense. I have not tensioned off the cables onto the deraileurs yet because I was afraid i was missing something.

 

Its fine.