I had an idea, and I think its good enough to share.  When you add skills to your LinkedIn page the reflex is to add as many as possible.  Who doesn't want to look, "skilled," at everything?

I am recommending add 2, at the most.  Long term, you will get endorsements and I’m thinking you will get more on the 2 for which you want people to see you as, “skilled.”  Then, over time add 1 skill at a time.  It keeps the page active.  And hopefully you pile up the endorsements for that new skill; repeat.

What is the downside to this?