Pros
I was recruited via LinkedIn as a management trainee and I had a unsettling feeling about the possibility that the job description the HR rep was selling me was too good to be true. Great entry-level pay and a structured, business management development training program? Me, a liberal arts grad? Turns out the pay is good for an entry-level job, the health insurance is great, and there's tuition reimbursement (if you stay here long enough to actually complete a course or a degree, which is a very depressing prospect). You'll lose it all though when you realize quitting is the only way you can retain the sanity you have left, or they fire you with little notice.
Cons
Absolutely soul-crushing, tedious work. It's also challenging. Challenging, boring work that has no meaningful impact, other than to enhance "efficiency" and lead to "productivity gains" (read: to justify staff getting fired) in micro-managed departments. Pretty much everyone I talked to at McMaster is cynical about their jobs. The so-called "management development program" isn't structured in any way (you're randomly moved around at the hand of some opaque authority), and it doesn't develop any applicable skills. The vast majority of people are there because it's the only job they can get that pays that well (especially for those with liberal arts degrees) or they need the tuition reimbursement to fund their business degree. If you're a graduate from a top school and want to build your resume, then surely explaining and justifying your position as a warehouse or call center supervisor to future employers isn't going to be the most appealing. Granted, you'll meet some great, intelligent people here, but they're more likely than not going to be jaded about the job. One of the managers who interviewed me actually told me "this isn't a place to work if you want to change the world." Hardly very motivating. This brings me to the toxic, hostile culture that is McMaster-Carr management. Everyone seems to be afraid of getting fired. There is 0 job security at this place. It operates on fear, especially for non-management. Feedback is not forthcoming, and when you do get any feedback, it's going to be negative. Get ready to be thrown under the bus during meetings, even by the manager who is supposed to be developing you. In terms of learning about how a business works from the inside, it's not a place where you're going to be inspired. The foundational software all departments use and rely on is an IBM program from the 1970s. It crashes almost every Friday, leading to huge delays in getting work done and shipments to customers. There are actually entire departments based on working around this awful, archaic software. Get ready to learn how to do "runs" to get data on an interface that looks like something out of Star Wars. Your recruiter might try to sell McMaster as the "Apple of industrial supplies". Don't buy it. Sure, there's a sleek new office, but it's intentionally designed like a panopticon (wikipedia it) so that everyone's work space is entirely visible and you never know if a supervisor is looking over your shoulder. You'll also be reprimanded if you have anything other than 1 pen and 1 drink on your desk. God help you if you have hand sanitizer on your desk, or if you leave a sweater on your chair. To give you some background: the company only recently started allowing employees to keep water on their desk. My advice? Work here for a few months if recruited and save every penny. Look for another job the whole time. If you look at it as a holdover while you look for a job worth doing, then it's great pay. This isn't a place to stay for longer than a year, unless you want a serious case of depression. I should have taken all these scathing reviews on Glassdoor more seriously before I committed to taking the job. Quitting this purgatory was probably one of the best decisions I've ever made.