Yes to a certain extent there is a rambling nature. First I meant what I said about the "forbidden topic". Mention it again and that will be the end of my participation in this thread, plus I will flag it for consideration for closure.
Frequently people have just enough knowledge to be "dangerous" which is the euphemism. In real life what this looks like is that Users get so wrapped up in what they DO (or think they) know, that they close themselves off to what they don't.
As I said (and I don't just type these words for the typing practice) it completely depends upon the process. If you have a specific problem with a specific process it would do well to describe that situation in specific detail rather than generalizing, because (as I mentioned) generally speaking, problems that require the User to terminate a process via Task Manager are almost always the result of malware.
Please tattoo that one in reverse on your forehead, and then spend about 20 minutes staring at it in the mirror.
Or, less often, the problem is caused by corrupted system files, which can be corrupted through MALWARE, overclocking, overheating, a failing HD, bad memory and other reasons I can't think of right now.
If a process will not stop, it will tell you so. If it is stops, then appears "instantly" as if it were never stopped, that is because it restarted very fast.
Itty Bitty Process Manager is an alternative to Task Manager, and you can use it to see if the problem is that TM is not stopping the process, or if it is just restarting.
If you are inclined to explore & learn about processes, I suggest that you play with Administrative Tools>Services and get a sense of what processes there are, which ones are Auto, Auto (Delayed), Manual and Disabled.
Please note that this is an excellent way to completely cripple your machine; almost as good as fooling with the Registry.
But again, in general, until you can describe specific situations with specific processes, my general opinion on whatever general causes of your problems is malware.
In many cases, malware infestation is like a diagnosis of cancer. The first stage is Denial. Then Anger. Then "Negotiating" and finally Acceptance. Please skip the first two stages and describe your AV solution.