How necessary is bureaucracy?
I will assume that you are asking about bureaucracy in government. Bureaucracy does exist in the private sector as well, but I will discuss government bureaucracy here.
Bureaucracy and bureaucrats generally get a bad name in our society. However, it would be completely impossible to run a government of any size without them. If we want to get rid of bureaucracy, we also have to stop having the government do essentially anything. Therefore, bureaucracy is necessary.
Presumably, we all want government to do at least some things. At the very least, government must provide security (policing and military) and provide such basics as good roads and schools. There is no way any of this could be done without bureaucracy. The reason for this is that bureaucracies are necessary in order to carry out government policy in a fair and consistent way. Imagine, for example, a military without a bureaucracy. You would have someone like the President set out a basic policy (for example, that we need to maintain a naval presence in the Pacific to deter China from being too aggressive) and then you would have all the individual naval units or naval personnel having to figure out how to carry out that policy on their own. This would end up in total chaos. With a bureaucracy, the top layers of the bureaucracy set rules and those rules are transmitted down the chain of command. This allows a policy to be set and to be carried out in a consistent way. This must be done for every government function from tax collection to highway building to the military.
Thus, a government without bureaucracy would be chaotic and aimless. Bureaucracy is necessary.