> The big advantage of driving to work over taking the bus is time
No. The big advantage of driving is reliability: I know that my means of transportation will be there, where I left it, at any time that I want it. How many of us have missed the CalTrain by a few minutes, only to have to wait an hour till the next one comes by?
CalTrain is decent unless there is a breakdown or as happens on average more than once a month, someone is struck by a train. If either of those things happen, the whole system shuts down and you can easily be two hours late. I don't know how to solve the problem, but it really sucks and keeps CalTrain from being a dependable form of transportation.
By building infrastructure new rather than utilising something that is not from 1863. I mean I am shocked the line isn't even electrified yet. Something that happened across Europe fifty years ago.
Then that's a poorly resourced and underused rapid transit system. A heavily used subway line can run trains every 3-5 min during rush hour (and on some lines, ridership is high enough that they'd run them even more frequently if safety allowed); a bus route, every 2-3 min; and commuter rail every 10-15 min. Even at 3am, my nearest subway line runs trains 2-3 times per hour.
Unfortunately, underutilized transit options are subject to a vicious cycle wherein it's impossible to justify running more frequent service for low ridership, and lack of frequent service suppresses ridership. Once you do have a strong public transit culture, it builds on itself and makes investment in frequency an obvious choice (not just for convenience but because you need more buses/trains to fit more passengers!)
Not just reliability but more so flexibility.
Want to buy some groceries on the way home? Planning to meet a friend for dinner or drinks? Trying to go that show you always wanted to see?
Most likely none will be on your bus route. Suburbia in the US is built for the car, not for walking or public transport. So most likely the (right) grocery store won't be near your house (nor your place of work). The restaurant or bar where you'd want to meet your friend will most likely be in another town nearby (but not on your route). And the (movie) theatre will be in the outskirts, next to the highway.
That's another advantage of Bus Rapid Transit over trains. It's much cheaper to run one bus than one train, and the vehicles are generally smaller, so they run more of them for the same usage, meaning you generally aren't scheduled to wait as long. Of course, things can still go wrong.
VTA's rapid bus (the 522) runs every 15 minutes at rush hour, and the non-rapid one runs every 11. Off-hours is every 20-30 for each, but that's still 2-3x as often as Caltrain.
No. The big advantage of driving is reliability: I know that my means of transportation will be there, where I left it, at any time that I want it. How many of us have missed the CalTrain by a few minutes, only to have to wait an hour till the next one comes by?