If you are like me, you either walked into your new lab as a PI, or plan to do so, ready to roll. There is a lot that needs to get done, but how long could it take, right?
Chances are, if you got a PI job, that you did a postdoc in a lab that was running full steam. I did both previous stops in labs of assistant professors who made tenure while I was there. In both cases, the labs were established enough to be just gaining a reputation for themselves, but hadn't fully broken through yet. By the time I left each, the story was different and each one had expanded significantly.
At the time it never occurred to me to consider the early days of each lab, but thinking back, each took some time to get established. However, walking into my own lab I assumed that in a year or two I would be DOING ALL TEH SCIENCE!!!!
Hhahahaha, yeaaahhhh. About that....
I'm sure there are people who do magic in a year or two and crap nature papers like they have some sort of scientific dysentery. Good for them. But for the rest of us, a lab is built in small steps with the occasional home run and the more than occasional strike out. It is torturous at times and progress seems glacial because you always feel like you are behind. But at some point (different for everyone) you can look back and surprise yourself at the progress you have made.