Hard to say why they did that. But it does sound like you need to have another go at it if they are not attractive. But that doesn't mean to you have to take them that low again.

You might find the link helpful. If you look in the upper left hand corner, there is a pdf link for the same document if you prefer pdf format for printing.

UGA CAES publications would be a great resource for you. Here is a link to the list of them.

Here is a link that might be useful: UGA CAES Basic principles of pruning woody plants

Great link. I bookmarked it.

Generally, "hard pruning" should only be done to remove dead or infected wood. Plants "know" how they're supposed to grow.

It is common with Crape Myrtles but that plant is actually more attractive as a small vase shaped tree. The technique has been extended to "topping off" large deciduous trees. The practice is frowned upon by true arborists.

It is more likely that the landscaper was
1) Unqualified
2) Looking to generated added revenue
3) Employing illegals who only know saguaros, not trees.