Expectations

Expectations can be a motivating thing, or it can totally ruin someone.

It's great to set goals and have hopes for someone in your life, but be sure to never set the bar so high that it's impossible to reach it. This happens a lot when you're relying on someone, they don't follow through, and then you're left in disappointment because they've failed in your eyes.
Maybe they've done the best they can do for you. Maybe what you were asking of them was too much to handle. Maybe they didn't know how to react, how to do, what to say, to what you asked of them.You're left feeling like this person didn't care enough, didn't try hard enough.

When expectations are a good thing, you're setting goals for someone to be motivated to reach. They set the person up to succeed. The bar is raised higher than it was before, but still in the area of being capable to reach... then the next objective is set after this one is attained. To whom much is given, much is expected.

Don't set someone you love dearly up for failure. You'll end up hurting both of you.
Instead, be thankful for the things they do for you, and use those as a guide to show you how this person is trying to love you the best that they know how.