Every thing we attempt has a "why" attached to it.
When we begin a new habit, we need results to keep us going, so that our "why" changes and adds to our resolve.
"Because I'm already seeing results."
This is why your foreign language studies need to be put into use immediately. Without that immediate use, it's difficult to keep going with Homeschool Spanish, (or with Homeschooling at all!)
As you begin (or continue) your Homeschool Spanish lessons and studies, be sure to stop and ask yourself again, "why?"
Putting words to the motivation behind becoming more influential in your world, or able to help more people, increase your reach, remember facts and events more quickly, and simply be quicker witted are ALL great reasons to learn a second language. What is YOUR "why," though?
I'd add to this: Homeschooling in GENERAL. For me, the Why is TIME. It's the one truly non-renewable resource. No matter what, you have TIME with your children, and that's something that is truly irreplaceable.