Timeline Section Shows "+X Projects". Why?

Timeline component positions the listed projects based on their Start date & End date (Project's Dashboard)

Our example project starts in 2016 and ends in 2020

If these details are not filled in the projects can't be placed and will be placed without start and end in the middle of the component.
There are 7 projects which do not have their start date & end date set

How did we do with this article?