I could write a book on how bad these companies are but I'll try to keep it short since nobody wants a tl;dr. Since the thought of them infuriates me and the classic BUMP copypastas usually come when I'm pissed, I'll try to make this one atleast entertaining. So sit back and relax (looking at you DoK, mono, AaronY, jeebus, etc).
First of all, I'll get to the elephant in the room. They hire any swinging off the street. There are even people that FAIL these exams (way below their "minimum company standard etc blah blah blah) and still get hired because they are so desperate for a warm body to fill a seat. The summer I worked there, we had a guy who was essentially a snake oil salesman. He comes in saying "I can tutor [insert handful of classes he was definitely not qualified to tutor]." The program director gives him the tests to take, he bombs all of them, but still gets hired because he convinces them "he's got this" and just needs to refresh. Sure enough, when the students come in, this guy regularly gets stumped with stuff as low as Algebra II. And this is not as rare as you might think either. The hours there are , and there's a surprising amount of guys who want to go there and work full time. By wanting full time work, many of them overextend themselves saying they can tutor way more than they're qualified for. (More classes you can tutor the more hours! they promise) Parents of course don't know this.
Also, it's funny because every company says they have the "secret formula" but it's all the same crap just copied and pasted from College Board with the questions rearranged depending on which company you go with. And the "high, rigorous hiring standard" these companies supposedly have is BS. Heck, I've gone to company websites where they say they only hire certified teachers with Master's Degree from top universities and then I'll go to Indeed.com and the same company will have a job opening that clearly says you simply need to atleast be in college with NO teaching experience required

Just outright lying.
What else do the parents not know? These companies have a business to run which means keeping as few tutors as possible and bringing in as many kids as you can. Which means you can have up to SIX kids per tutor. And you'll be paying the same, oftentimes a higher price than a private tutor for your kid to receive maybe as few as 20 minutes in a 2 hour window depending on the needs of another student. Hopefully they don't have a big test coming up! All this when the tutor is not anymore qualified than a private tutor. Oftentimes less so because all the good tutors at these places will eventually leave once they see what a scam it is. Did I mention price? Yep, it's just as expensive as a private tutor because they need to keep the lights on as well as paying the office assistants to sit around and browse facebook all day. Last but not least, since they'll take anybody in, they will regularly mix high school kids (with an upcoming SAT on the horizon) with two 3rd graders who need to be babysat while screaming, running around, and making paper airplanes. What a great atmosphere conducive to learning for high schoolers!
I say all this but there are a few good tutors at these places who, only God knows why, choose to work there long term. It's usually 2-3 long term tutors with 8-10 guys who are there 3 months max so your kid will never be able to sit there and develop a relationship with the tutor because the lifers are always reserved while everybody else is just a revolving door. If your child only needs a little bit of HW help and is an absolutely terrible SAT/ACT student who would never have the discipline to study on his own without having his hand held, then maybe you will get something out of it. But everybody else is getting royally screwed out of their hard earned money and the people who run these centers should be rounded up, shot, then covered with fecal matter. Other than that, these tutoring centers are great!