Kinda sums it up for me, except I have several "niches" or purposes (only two of which are filled at the moment), and I like variety, so I'm not sure I'd be happy with JUST one bike:

- commuting/transportation.
- coffee shop / grocery run (fun, stylish, shiny, fairweather) - my equivalent of having a classic old sports car for driving on nice days.
- Recreational-road -
- mountain bike/ winter commuter

I dont mind putting money into these bikes, and would rather have three or four really nice bikes than 10 mediocre bikes.
That said, I do love to wrench, so I can picture a number of other bikes coming through (for flipping).