I have just 6 domains, 4 .com and 2 .info domains. When I decide to buy a domain is becasue I like domain name and know what to do with this domain.
I dont buy domain just to keep in my domain library.
I currently own 8 domains...of which I will retain only 3 and drop remain 5...those 5 are useless! Those other three domains are currently used for my sites...2 of which are working...3rd one is under construction.