You could fix it if you have to, and sometimes you do. You could run Intersect Faces>With Model to intersect the component and group with the rectangle on the ground and then delete the stuff under the component and group.
If you want any sort of efficiency when you are drawing you should work on consistency in the way you work. The Push/Pull thing is a good example. Staying on top of reversed faces is another. Another thing in your example: why is one of the things a group while the other is a component. They probably ought to both be groups or both components but not one of each.
You need to learn and use good habits as with anything else in life. And the only way to do that is practice. It will come, though.