“Competitiveness” is commonly used when we want to describe how transit matches up with other modes, particularly the automobile. The value of transit competitiveness can be quantified in different ways, but travel time is most often used as the proxy, at least in the simplest terms of discussing how transit competes. If a rider expends 10 minutes traveling between Point A and Point B aboard transit versus 12 minutes driving, we like to say that transit is competitive in that instance.
Of course, using travel time alone is probably a poor way of describing the breadth of how transit competes. Cost, comfort, reliability, etc. are all variables that should be taken into account. As such, the Puget Sound Regional Council (PSRC) does have what’s called a Transit Competitiveness Index— a composite index that takes into account a multitude of factors in quantifying how transit competes with automobiles for any given origin or destination in the region.
At any rate, the problem with using competitiveness as a measuring stick of success is that it’s constructed on the basis of a singular rider experience, instead of an entire population, which is what transit is designed for. If we try to minimize the travel time for that rider between A and B, it’s probably at the expense of the riders who live in between those two points. Similarly, if we try to maximize comfort for each individual passenger aboard a transit vehicle by providing cushy armchairs, it means less people can get on that vehicle.
I think that where applicable, transit competitiveness can be appropriately used as a marketing tool, but it shouldn’t be the be-all end-all of how we plan our network. Ultimately, people care less about lining up their mode choices side by side and judiciously selecting the most optimal one, and more about whether or not transit can meet their needs. As long as that criteria is fulfilled, then our primary concern should be maximizing it for as many people as possible.