A component that doesn't have direct customer value — that's how I define a checkbox feature. You see, there is some list, put together by someone involved with the organization doing the software development, filled with vague, must-have features. The urgency with which these features actually need to be developed is non-existent, outside of this arbitrary list. The acceptance criteria, for having completed any of these features? You get to check the little box beside the list item. While not exactly useful, to anyone really, this checklist of capabilities looks darn impressive when used in a sales or marketing context. The inherent problem is that these features don't really solve a specific customer-facing problem. A given checkbox feature may be enough to get your foot in the door, but you also need to be aware of side-effects.