* This is, at its core, a call center job. I felt like it was probably among the better call center jobs you could ever get (attainable metrics rooted in logic, largely pleasant customers, functional systems, etc.), but you are really subject to what any call center is subject to. That is more negative than positive. You will be sedentary for 8 hours per day and have limited personal time. They have a strict attendance policy and if you need to leave mid-day, there are ramifications for it. Your work can feel very unappreciated, and the errors you make will scream a lot louder than all the good you do.
* I am very, very lucky to be single and childless. There is little understanding for those who have to take care of families, particularly in regards to the rather draconian attendance policy. Those who are in attendance trouble are nearly exclusively those who need to use days off to take care of sick children, and I've seen several exemplary peers leave because they needed a more flexible job. Likewise I mention a lot of promotions above, but I find most of those people to be childless. This is not discriminatory but rather a somber truth that the attendance policy does not work well for those with kids.
* A lot of your fate is in your manager's hands. If you have a poor relationship with your direct supervisor, your career at UHC may be done before it starts. The stats are your baseline, but there will be a lot of people who make their stats. Those who get plum projects, promotions, and acclaim in the department are those who best work with their managers who will put their names out there. Usually, there's 2-4 people per "team" who get that kind of push, to the detriment of others. I was very lucky to have the skills to get in that position. Other very strong peers never get that shot. With the way feedback works, you often find out what you did wrong when it is too late to fix it for the opportunity you wanted.
* Promotions. As I said above, there are opportunities. Just a few things to know up front. The general rule is that it is a year before you can "post-out" to other departments. That is true, but most people who get promoted don't see it until they're a couple years in. If you go in thinking that you'll put in your year with the headset and then find a higher up role...good luck. Additionally, competition is very strong and there is a lot of luck involved throughout the process. Your promotion may hinge on finding the role quick enough, getting the right interviewers, etc.
* Feedback and Fixes are a long process and a problem. There is a once a year survey that doesn't seem to affect much change, feedback isn't well received and any process or protocol changes are laborious to get done. The second another department or a really high level manager needs to get involved, the hope of change dies out.
* It can't be a UHC review without mentioning the health insurance. Yes, it's all high-deductible health plans. You can leverage those to your benefit, but the main perk of the plan is that it is very well subsidized. There is no higher premium/lower deductible option any more.