Why does the word "bureaucracy" have a negative connotation?
The word 'bureaucracy' is perceived as that branch of government that slows processes and implementation.
In most systems of democratic government, the bureaucracy is the executive branch of the government (the other two being the legislative comprising elected/nominated representatives, and the judiciary).
The bureaucracy is responsible for carrying out the legislative or judicial decisions. It has a system of rules and regulations that is often perceived to impede implementation as well as processes that are meant to enable a citizen access rights. Common terms that describe this are red-tape, paperwork, protocol, etc.