Some western historical professors call it "Mao's last revolution".   And Chiang's regime taught pople in Taiwan that Mao was afarid of losing power to Liu, so he initiated the Culture Revolution to get rid of Liu.  This is not true from my study of the history.

After Mao successfully led the troop 25000 kilemeters long march to be out of danger of KMT force. Plus Mao also kicked Chiang out of mainland China.  No body would have the strength to challenge Mao authority. Liu was just one of his capable subordinates .  The conflict between Mao and Liu began when Liu criticized Mao policy to cause the people suffer (The root cause of the people suffer was from the middle level CCP officers did not do a good job). Then some of the CCP members agreed with Liu and tried to correct Mao's policy.

Mao saw this issue way beyond the surface. He viewed the problem was caused by many of his CCP high officers' corruption because the power included Deng, and eagered to use capitalism to improve their and people living standard. These were the threat of his communism ideology and CCP. By his own word: the issue is the conflict between communism and capitalism.  Plus he could not tolerate Liu's critism. So he initiated the Culture Revolution to punish his high rank comrades for their corrupted capitalism thinking and tried to get rid of bad elements of old Chinese culture.

Eventually it caused the chaos of the China, so he then called Deng and some of his old comrades back to put the society back to order.  To say Culture Revolution is solely caused by Liu was not even close to the truth.

Recently Taiwan has a corrupted ex President Ah Bein, fake shooting before the voting day  and the wrong trial to put an innocent solider to death 15 years ago. These all have to do with the bad elements of old Chinese culture.  That is why I say you need a Culture Revolution to correct the above problems.

See here for reference and this link