Anon had a good comment (here) that included:
Sure, everyone needs to decide for themselves what they are willing to put up with and how far is too far to compromise. But if this were my former trainee, I would be asking her, what, exactly are you getting from this position that you couldn't get somewhere else?
A postdoc is not and should never be looked upon as an end within itself. If Cathy is unable or uninterested in making the leap to PI after 5+ years of postdocing, it might be time for her to implement Plan B.
I started answering this in comments, and it grew into a blog post. So.. here you go. (this info is with Cathy's permission, with some details changed to hide identities).
Anon, your points are good. And they may be appropriate for some (significant) subgroup. But they may not be, are not, where Cathy is now. If Cathy was in her 30s and single and childless and generally responsibility free, yup, Plan B is in order. And even if she could hit two of those four, it would be ok. But she's not. She is in her late 40s-early 50s. She has teenaged children, and there are child concerns that would make moving more significant than just moving. She has a spouse who has a near ideal job, and one that pays very well. They are in a mid-sized mid-west city that suits both of them, and have a good network of friends and support and community. Needless to say there are not a lot of other academic games in town. She and I have talked about this over the years since she left my lab.
Further, Cathy is not a postdoc. She's a non-TT professor, with skills that do not immediately translate into industry. So The research is beyond interesting to her, its compelling and she has made a strong commitment to it, in terms of being able to Make A Difference In The World (which is something that is important to her).
So when she asks what she gets out of this, her answer is not just "a job", but "a job I really love, in a place I'm not willing to leave, with great benefits, both from HR and intellectual".
No position is perfect. None. I've had enough to know that is true. And the decision about when it is time to leave or leap or pull the trigger or even slink out of town in the middle of the night, is not just tough: it is a multivariate equation, with a matrix of personal weights that vary from individual to individual. I used to laugh (when I was young and foolish) at colleagues who said "I will only take a job in New York City or San Francisco". What kind of academic are they, I'd think? But now, I am not so quick. There are things that are important to each of us that means maybe we only want to live in Big City, but also there are lots of folks who only want to live in Small Town America. Hell, I changed jobs, as an academic, when the chance arose, to go live where my aged parents were so I could take care of them. I also know that the older you are, the harder and harder the moves get. Physically, psychologically and professionally. Let alone the burden of finding a job in your 50s.
And while the commenter, and others I respect, say that a post-doc (or non-TT position?) should not be an end in itself. I am not so sure. Yes, there is potential for abuse. Yes, such a position is not as secure, as well paid, etc. But there are people who do not want to be a Bigdog PI. Ever. They are content, for whatever reason that is different from you and I, to be an "extended postdoc", to be a research professor, to be a glorified tech into their 40s and 50s and 60s.
Part of the point of my post was that Cathy has already decided that the job is worth it to her. We had a long, long talk about this. We had a long talk about options. She is well aware that a non-TT job is not as secure as a TT job. I think that if a TT job was available, she'd jump on it with all she's got. But that's also assuming that any department would consider hiring a 48 year old or a 52 year old as a starting TT professor.
Part of my discussions with her, and these posts, are when that decision has been made, the decision to stay, what do you do next? It is a worthwhile effort to ask the question about staying, to look hard at stay or go, but we all have to understand that each person will answer it for themselves. And with that answer, my goal, is to figure how to make it work.