Buses require a circuit to operate, unlike cars which can operate in single-vector mode. Thus, they can be impacted by seemly-non-systematic events such as distant traffic in the other direction.
It's got nothing to do with traffic delays. There are plenty of buses at each leg in my route. My specific problem is that I have to ride for 20 minutes in the opposite direction to get to a transit station where I then transfer to an express bus out to UW Bothell. But the bus from UW to my office isn't synchronized with the express bus so I either wait 15 minutes or walk a mile and a half across I-405.
On the other hand it's very efficient for getting in to the city, as I can hop on a single bus and be in Green Lake or the U district in about 15 minutes, and it's another 10 to cross the canal.
