I booked a couple of models once for a magazine shoot (not through MM but a UK-based site) commissioned by a third-party client. Both had worked with one another before and the images in their respective portfolios confirmed they were exactly what the client was looking for.
The shoot was 'top-shelf' magazine G/G style and the client one of the major UK publishers of such material.
Stupidly (in retrospect) I booked them without thinking to book additional reserve models 'just in case'.
One was fine and more or less as per her portfolio, the other had unfortunately neglected to inform me that since the last image in her port had been uploaded, she'd become a mother to twin girls with the resulting collateral damage to her figure: she was at least 20lbs heavier, her breasts had gone up at least two cup-sizes and the stretch-marks were unfortunately impossible to disguise given the type of shoot we were contemplating. This was in the old pre-digital days - the shoot was on medium-format tranny film and the retouching costs would have been astronomical.

I appreciate not all women can easily lose the weight that pregnancy often inflicts upon them, but as a model you kind of need to be up-front about it.

Needless to say, the Client took one look, cancelled the shoot and fired me on the spot.

To me it's important that the models I shoot with DO HAVE images on their profile that's up-to-date and that they also DO HAVE images that are NOT heavily retouched. I like to have some idea of what to expect.