A shortlist is a list of the best things or people, chosen from a longer list.
A shortlist is a good thing because it means you are close to choosing the best thing or person.
Examples:
The shortlist has the best players on it.
I will shortlist the best ideas for the project.
She made a shortlist of the top three cakes.
I need to shortlist the best toys for my birthday.
The shortlist for the job had only three names on it.
We shortlist the best movies for our movie night.