When the whites go the jobs, infrastructure, etc. goes with them.
Why?
Good question, we have been asking that question for decades.
It shouldn't take you that long to figure out the answer. It's not complicated, but I'll give you a hint; you're here doing exactly the work that the people who want to keep blacks down want you to do.
What i find amusing is that the most racist folks always seem to know more about black folks than we know about ourselves.