Make all transitions have black background

When using a video transition, most of the time my clips are touching each other on the same track. when I add a transition to the front of a clip, it transitions with the previous clip being in the background. But sometimes I do the exact transition to a very similar spot on the timeline and the previous video is not displayed during the transition(the background is black). I am doing nothing different and I don't see why most of the times the transitions use the previous video but sometimes, randomly it seems, the previous video is not displayed and a black background is displayed.

I want to be able to control when this happens as I do like the black background.
I am 100% sure I am using the same transition, on the same type of clips, in the same project, the transition box is in the same spot on the timeline, etc ,etc. It really seems random.

JUST FIGURED IT OUT!! lol

So the transition has to be added to the clip while it is NOT touching the previous clip. Then the transition will start with a black background. Then you can move the clip with the transition next to the previous clip.

But obviously this is more work, can anyone offer a quicker solution?