By the 1990s it began to dawn on the Chinese that none of there potential enemies were likely to be defeated by a steamroller approach. Taiwan needed an amphibious and airborne attack, the India frontier was high in the Himalayan mountains and no one was sure what the Americans might due, but it would be different and high tech.
The Chinese decided that since they couldn't upgrade their entire armed forces (even after demobilizing half a million troops over the last few years), they could begin building smaller, more capable units. The capstone of this program has been the formation of mechanized infantry, tank and artillery brigades. The Chinese had long used the division as their primary battlefield unit. The 22 new brigades were a third to half the size of a division, but with more modern equipment, more strenuous training and a doctrine that emphasized rapid movement, quick thinking and independent decision making. All of this was alien to Chinese military thought over the past half century. But the Chinese realized that a few well trained troops getting to a trouble spot quickly would be more effective than sending in several divisions a month later. These Rapid Reaction Units (RRUs) are meant to be able to move out on a few days notice. Most Chinese divisions require at least a week (usually a month) to call up reserves and get organized for operations in some distant part of the country.
Brigades were formed by tanking divisions, often motorized divisions, and demobilizing the least capable two thirds of people in the unit. The troops left were enough to form a brigade. Unfortunately, the increased tempo of training meant a lot more work for the NCOs and officers, without any prospect of reward. The new brigades were expected to lead offensive operations and perform long marches through the wide open territory that characterizes much of China's borders. Running one of these new brigades was a lot more work than being in one of the older divisions. With the economy booming and employment for energetic young men easy to get, many of the junior leaders in these brigades left the army.
Part of the exodus had to do with attempts to get army officers out of business and back to soldiering. Before the reorganization, divisions and armies were attached to military regions (an area containing one or more provinces) and these units rarely left their region. They were expected to get their supplies and much of their equipment from their region. To help in this, each military region set up its own farms and factories to supply the troops. When economic reforms were enacted in the 1970s, the army found they could make a little extra money by selling some of their production to civilians. Then the officers realized that if some of their factories produced civilian goods, the officers could make some real money.
In the 1990s, the government shut down many of the military factories and farms at the same time they were reorganizing the divisions into brigades. A lot of officers and troops realized they preferred being in business. All this hard training with the new brigades was not what they were all about. While a lot of hotshots left, the high unemployment in rural China made it easy to recruit new men. But the new guys were not that well educated, although many were eager. But the new "blitzkrieg" type of army the brigades were meant to fight could not be done unless the troops were well educated and trained. The new men were willing, but making them able was going to take a while.
Corruption and soldiers having second (civilian) jobs is an ancient problem in China. Many of the senior political leaders recognize the problem, but are having a hard time solving it. Many of the most able military officers get out, disgusted with the corruption and slender procurement budgets. As a result, the military talent pool is pretty thin. The 22 RRU brigades, the 15th Airborne Corps and special forces (ranger/commando) brigades form an army within the army that is more reliable, but also drains the rest of the army of its most capable people. The other 70 percent of the army is pretty spotty when it comes to combat capability and reliability. Keep that in mind when you see any mention of China's 1.5 million man army.
In the last five years, China has been trying to reform and reorganize its army to deal with something less than total war. After the Korean war, when Russia came to be seen as the major enemy, the armed forces were organized to operate partly as a guerilla force and partly as a lightly armed army. This was supposed to allow China to deal with the better armed and equipped Russians the same way the communist armies had the World War II Japanese. This approach also recognized the fact that China could not afford to modernize the army anyway. In the 1980s, with the economy improving and Russia no longer the enemy, the armed forces got a lot more modern equipment and abandoned the guerilla war angle. But because the army didn't have a lot of modern weapons, the only tactics available involved massive attacks. Sort of like the Russians in World War II. The Chinese figured that if this approach enabled the Russians the defeat the Germans, then it would work if China went against any potential enemy.