It just depends on the type of information you’re working with. Is the document important or is the information about that document is required? So for example, if you need to keep track of registrations for an event; it would be more efficient to have them in a Custom List as you can create views to see how many people have accepted or declined, all their contact details, dietary preferences, bringing partners, etc.
But if you were working with contracts and you have multiple people working on the clauses, a Document Library would be more efficient with a few columns to quickly categories what type of contract it is, who owns it, what version it’s on, check out check in functionality, etc.
If you want to bulk upload documents, document library has open with explorer option where you can easily drag and drop documents, which is not available in list.
For more information:
http://veroniquepalmer.com/2013/02/24/the-difference-between-sharepoint-2010-lists-libraries-and-pages/