Why do people do Smith machine squats? They're not safe, like people seem to think...they're more dangerous than squat racks. Squat racks have safety racks so you can drop the weights at any time. Also, the weights aren't locked in, so you work your stabilizer muscles, you have the option to dump the weights if no safety bars are available (though I wouldn't recommend it), and Smith machine squats are an unnatural motion that will destroy your knee joints. I should know, because my idiot physical therapists made me do Smith machine squats after all 3 of my knee surgeries and they only made things worse. However, I'm progressing great now that I'm squatting a bit below parallel with free weights. I usually like ATG, but my knee flexibility sucks :/