The Seattle Times' Mike Lindblom has a front-page story today laying out some of the reasons why RapidRide, the "bus-rapid transit" line to Ballard, isn't so rapid, with speeds averaging just a minute faster than the local 15 bus route RapidRide replaced.
Among them: A lack of signal timing that would give buses priority when moving through intersections (also known as "queue jumps"), separate lanes for buses, at least during peak hours (currently, buses sit in traffic along with everybody else), and a lack of coordination between the city and Metro on utility construction projects.
I would add a few more reasons:
1) Neighborhood opposition to any transit improvement (such as bus bulbs) that takes away parking for drivers (see, for example, this panicky KING 5 story about how RapidRide "has some residents concerned about parking and traffic";
2) Rider opposition to longer spacing between stops, which greatly improves bus performance (riders complained about having to walk further on the new system, prompting Metro to put stops closer together along some parts of the line;
3) The lack of level boarding, which would allow riders, including those in wheelchairs, to board quickly and without the need for a retractable ramp; and
4) Metro's failure to implement off-board payment, which would speed boarding by allowing riders at many stops, not just two, to pay with their ORCA cards before they get on the bus. (Currently, the two ORCA readers Metro has installed aren't working anyway.)
In short, opposition from NIMBYs and riders expecting door-to-door service derailed Metro's plans and turned BRT into a system that's basically a regular bus line, only shinier.
Of course, we (and Metro) already knew all this: Bus-rapid transit only works when transit agencies make improvements that help the system function, sometimes over objections from opponents; simply throwing more buses at the traffic problem never works.
What does work? A real bus-rapid transit system like the (frequently lauded) one in Curitiba, Brazil, which includes frequent service (every 90 seconds during peak hours on some routes), dedicated busways (no competition with cars), off-board fare collection, easy boarding via extra-wide platforms that can accommodate wheelchairs, and express routes with less-frequent stops.