Pros
AT&T is 250,000 employees; your experience will vary greatly depending on what part of the business you're in, who your boss is, and the cultural of your department. I've been on the management side for my career, and generally found people helpful and wiling to lend a hand. AT&T is a good place if you're looking for that one firm where you can spend the majority of your career; the place is sufficiently complex that simply learning how to navigate that complexity makes you a valuable commodity - even in roles where you may lack the primary experience required. As long as you don't get stuck in a dead end group, many people change jobs frequently and build relationships throughout the firm.
Cons
AT&T is primarily looking for moderately competent managers to drive the business forward in roughly the same direction it is already headed. It's also nearly impossible to get fired here. The bureaucracy here can be intolerable. I served in the military, several years of which was spent in a mixed military/civilian office, so I have a good feel for the civil service portion of the federal government. AT&T is in some way more hierarchical than the military (junior staff are provided extremely limited authority; every decision must be made at an absurdly senior level), and more bureaucratic than the government. At AT&T, like the government, there is a process for everything; unique to AT&T is the fact that process likely isn't written down, is passed down by oral tradition, and it's never clear under whose authority. But good luck getting anything done if you don't follow the mythical undocumented process. In terms of employee quality, you have to go back to what the core strengths of the firm are. At Google, the core strength is their technical talent and so they hire and pay for the best - being a good software engineer at Google makes a big difference to the bottom line. At McDonalds being a really good cashier isn't going to have a measurable impact to the bottom line; sure I could hire a Harvard MBA, but he's only marginally better than the minimum wage guy. At AT&T the core strengths that make the firm profitable are low capital costs and incumbency (we spend $20B a year on our network - good luck trying to catch up). You'll notice people are not part of that equation - they are necessary to keep the company lumbering forward, but they are not a key component of competitive advantage. So the firm doesn't really need people who are that good, and certainly isn't going to pay to retain them. Being a top tier employee here is like being the Harvard MBA cashier at McDonalds - sure you're really good, and you make the customers extra happy, and you came up with a clever way that increased productivity at your cashier station by 20%, but at the end of the day you're just not worth the extra $100k a year.
