What is boredom?

Arthur Schopenhauer said that boredom is the very evidence that life is meaningless. He says once we meet all our needs, boredom sets in and reminds us that there is no true value in existing. Others have argued that boredom is a natural consequence of seeking happiness and contentment. Thus, if we are bored, it is merely because we are discontent but should hope to be engaged in finding content again. So really, I just want to know, what is boredom? Is it a precursor to addiction? Is it bad? Is it good? Is it neutral? What’s really going on when someone is bored? Any and all thoughts related are appreciated.