If I'm someone who has just paid a carrier to put a payload in orbit (or if I'm the commercial carrier, for that matter), I end up paying for every extra minute in orbit -- even before traffic loads are high enough to "need" the launcher back on time. This in itself discourages investment in new markets from day one, even before significant traffic volume exists.
If traffic volume to orbit does start to climb, the guy waiting to use the launcher next will be losing bucks (and getting madder by the minute) if the launcher is stuck in orbit for extra hours -- let alone days, or let alone there is some need to transfer it from a remote landing site it has been "waved-off" to land at instead of its launch site. With this sort of business uncertainty, the next guy in line to use the launcher won't be there; he can't afford to take a risk on a new market under these conditions.
How many commercial aircraft are, or have ever been, gliders? Obviously nobody will invest in delivery of cargo/people unless time advantage is a key market driver. If people/goods to and from orbit are considered as a market, then nobody will ride a glider, because the delays will cost so much money in traffic backup.
The contractor proposals for the proposed X-33 should have been just the inverse of what they were: mainly VTVL, with VTHL only a shaky possibility, instead of the other way around. Obviously the X-33 proposals were overwhelmingly driven not by any expectation or desire for legitimate private markets, but by the expectation of one dominating limited customer forever -- the government. Too bad for driving down costs; too bad for opening the frontier...
v.1 Monday 4 April 1995