When I was in my twenties and leaving the first full time position I ever had for a new position at a company I’d never heard of one of the VPs listened to my concerns and told me to take the job. She said if it didn’t work out I could always come back to my old job. That provided me a bit of comfort but she also told me that as I people get older opportunities tend to dry up.
Now I think of this in terms of open doors in front of me. I know now that if I do not pick one to walk through they could all close in front of me and I will be stuck in the same spot for a long time. So now I try not to miss the window of time when the door is open. The trick is to figure out which of the doors stay open the longest.