In many ways, the definition of public transport, is a system of travel taking you from one place you don't want to be to another place you don't want to be. Unless, of course, you're a fan of airports, railways stations and bus stops. This isn't to suggest public transport is unnecessary or unwanted, merely to observe one of its biggest weaknesses. Even in London with probably the world's most comprehensive and widespread urban system, this inconvenience is only really conquered in the two inner zones.
This issue is compounded by the nature of employment:
A telling reality for proponents of increased public transport investment is that employment remains – and in some cases is increasingly – suburban by nature. Between 8 and 9 out of 10 of all jobs in metropolitan regions are suburban by location, and when you consider that the same proportion of residents in any metropolitan location are also suburban by residence, the problem of servicing this reality through public transport is apparent.
You don't believe this? Well think about your London suburb. About all the jobs that don't involve getting on the train, bus or tube and heading into town. The people working in shops, for borough councils, primary health, hospitals - even manning those railway stations and bus depots. These people don't fit that classic commuter model and, in most places, don't match to a cost-effective mass transit system.
This is why - for all its faults and flaws - ride-sharing (using whatever model) represents a valuable contribution to reducing urban congestion. It makes little or no sense to set on a bus for the journey a particular commuter is making to get to work, except that there are perhaps ten or a dozen others making a similar journey. To kill off ride-sharing models on mostly spurious (and essentially protectionist) regulatory grounds makes absolutely no sense at all - yet that is precisely what many (if not most) city authorities and public transport regulators are doing.
For me the most telling statistic - the one that tells us those billions bunged at public transport won't solve the problem - is that over 80% of journeys are made in private cars. And when it comes to commuter journeys nearly 90% of journeys use this form of transport. There isn't the remotest prospect of us building sufficient public transport capacity to make anything but the smallest impact on the congestion those car journeys make.