re: "Should I close contracts that clients still keep open although the jobs were delivered successfully and were paid? Clients are unresponsive despite I had asked to close the contract."
If I do not have any work left to do on a project, or even if I have finished work for now and there probably won't be any work for a few months, I always ask the client to close the contract. And if necessary, I close the contract myself.
It is best to have a client close the contract, because that ensures that the client leaves feedback. Contracts without client feedback can negatively impact JSS if there is a significant pattern of them.
And you don't want to have a ton of open jobs that make you look busier than you really are. Also, having lots of open jobs that you aren't doing any work on will lower your "Long Term Clients" score, which is one of the specific metrics considered in calculating JSS. This number is not as significant as other metrics, but having a high Long Term Clients score CAN help JSS. And having lots of moribund/inactive contracts will lower your Long Term Clients score.
