I have kept so, so many breeds over the years for so many different reasons!
I think that covers about all of them.
Note that production has never been a priority for me with my flock, so has never really been a factor in any of my decisions. More what I am interested in are birds with good temperaments that are hopefully at least somewhat interesting to look at (solid white and buff are the main two varieties that come to mind as not qualifying for that requirement for me) and don't have traits that I dislike in chicken breeds (I think the only real deal breaker for me is large crests, though, like with Polish and many Silkies). The breeds (or "breeds" as the case may be) that I intend to always keep around are my precious silkied Cochin bantams that I am breeding for improvement based on the standard, my beloved Silver Gray Dorkings and Silver Duckwing variant OEGBs because I simply adore their temperaments and their appearance, Black Copper Marans (or possibly other varieties of Marans) for pretty egg colors, Barred Plymouth Rocks for sentiment and appearance, and Easter-eggers and naked necks just for fun and variety. 
- Some were just what was available at the time (red sexlinks, an amberlink, Gold-laced Wyandottes, a Black Australorp)
- Some were gifts or rescues (Gold and Silver Sebrights, Speckled Sussex, Partridge Plymouth Rocks, a Splash Marans, Rhode Island Reds, Swedish Flower Hens)
- Some were because I liked the looks of them (Barred Rocks, Lavender, Blue, Chocolate Mottled, and Crele Orpingtons, a Light Brahma, Fawn Silver Duckwing OEGBs)
- Some were because I wanted the egg color for my egg basket (Black Copper and Wheaten Marans, a Blue Ameraucana, a Welsummer, Light Brown and Exchequer Leghorns, an Ancona, an Egyptian Fayoumi, a Silver Lakenvelder, a Golden Campine, Cream Legbars)
- Some were because of their reputation for good temperaments (Silver Gray and Red Dorkings, large fowl and bantam Cochins, the OEGBs kind of fall into this category as well)
- Some were just for fun (Silkies, Easter-eggers)
- Some were mix-ups or substitutes in orders (a Bielefelder, Dark Gray Dorkings)
I think that covers about all of them.
Note that production has never been a priority for me with my flock, so has never really been a factor in any of my decisions. More what I am interested in are birds with good temperaments that are hopefully at least somewhat interesting to look at (solid white and buff are the main two varieties that come to mind as not qualifying for that requirement for me) and don't have traits that I dislike in chicken breeds (I think the only real deal breaker for me is large crests, though, like with Polish and many Silkies). The breeds (or "breeds" as the case may be) that I intend to always keep around are my precious silkied Cochin bantams that I am breeding for improvement based on the standard, my beloved Silver Gray Dorkings and Silver Duckwing variant OEGBs because I simply adore their temperaments and their appearance, Black Copper Marans (or possibly other varieties of Marans) for pretty egg colors, Barred Plymouth Rocks for sentiment and appearance, and Easter-eggers and naked necks just for fun and variety. 
She is so beautiful though, and lays lovely milk chocolate coloured eggs. But what a diva!!
