Whenever an item’s description is long enough for the “Show More” / “Show Less” button to be visible, the button’s words will cover up the last words in the description.
This also happens for user profile About sections, and presumably wherever else this button is used on the website.
Can confirm this, and not just with asset descriptions, it also happens some people’s profiles due to their amount of information. So basically this can happen to anything that has a description.