I don't have good luck with models.

[Richard Bingham]

Don't give up, Jeff. Thing is, since we're all human, (artists and their models) some days are diamonds, others are stones. I can empathize with your having paid the model off, sending her home, but a more fair ending would have been to have paid her for part of an hour for showing up, then dismiss her for not being in form, re-scheduling a new session with the understanding that she has a contractual obligation to "perform" to definite standards to earn the compensation agreed upon.

If you have access to people willing to work as models, you are now an employer. Tough or not, you have to set the rules, for the models as well as other participants, and enforce them.

Modeling is hard, physical labor which requires dedication, performance, and an unimpeachable work ethic. Past that, not just anyone can do it well. There's far more to the proposition than merely holding a pose, and sometimes verbal communication between the artist and the model brings it out . . . if you can't engage in conversation with a model and work at the same time, then a model who works better in silence is the one you use. When other people are involved, a very different dynamic often becomes very obvious in the model's demeanor. The more "players", the more complicated the situation becomes.

I am really in your corner, I too am fed up with "Drawing 101 5-minute poses", realizing that past a certain point, all they accomplish is an opportunity to learn how to begin a drawing.

Hiring a model, you have to be realistic about the models' capabilities and comfort, balancing that against demanding they meet your reasonable requirements. Difficult poses, pressure points on a foot, a leg, a forearm, etc., can require decreasing, shorter times on pose through the session, and more frequent breaks. Beware of the breaks! Most models will tend to stretch them increasingly if the length of the break is left up to them. Always set a timer.

Finally, realize even the best models will "sag" toward the end of a three-hour session, even with frequent breaks. A good plan for difficult or tiring poses is to split the session between two different poses, with the plan for returning to them in subsequent sessions as more working time is indicated.

Life sessions with numerous participants tend to "drift" if specific goals aren't set for each session before it begins. Props, drapes, pose, the purpose, participant positions and the time format should all be in place at the beginning of each session . . .

Lastly, I'd suggest paying incentives for exceptional models. In any case, don't be "cheap", but start at the low end of the scale, then reward experience and good performance with raises!