Companies are forced to seek long-term partners ([term][1]) if they think to live for years and keep up with all costs. 

Are we, freelancers, forced to do the same? Or since our costs are at the minimum and there is a lot of job (especially in IT area) we should not stick to long-term clients?

I am not sure if I am a grunch, but I better deal with new clients and their projects seems more interesting. Because with long-term clients I am somehow "forced" to take any project they offer me and I cannot reject them by saying "that project is boring". With new clients, I have no such issues since I only chose projects which are interesting to me.