The Economist makes some cogent points-
The generals are likely to notice two things soon. First, that they cannot rule the country unless they are prepared to use force. Secondly, beyond the walls of the barracks, Thailand has undergone a dramatic transformation, even since 2006. It has moved away even further from being the kind of rural agricultural society with its social relations defined by hierarchical, paternalistic relations. More each year, it resembles a modern state whose individual citizens and social groups look out for their own interests. Social changes that took hundreds of years to emerge in European history have taken just half a century in Thailand. That is less time than the average age of the generals who are trying to revive for Thailand a brand of authoritarianism that was derided as being reserved for the kingdom’s poor neighbours, Cambodia, Laos and Myanmar.
When Thailand’s traditional elites made it plain that they did not know how to run the country in 1997—the year the Asian financial crisis cut short Thailand’s economic miracle—the public began to seek greater power and influence for itself. Mr Thaksin happened to be in a position to serve as their vehicle. A thriving oligarch when he came to power in 2001, he built a political machine that ran on a simple principle: find out what people want, and give it to them. He was wily and absolutely ruthless, and he knew to jump on the train that was already rolling.
This is the underlying force that the generals have to contend with: not Thaksin, but the dramatically changed society that stubbornly brought him to power.
General Prayuth does not look like a strongman to reorder Thai politics and society. Rather, he looks like a soldier who got fed up dealing with hopeless politicians, and then pushed by his arch-royalist superiors into doing their dirty work and binning electoral democracy
Military coup in Thailand: The darkened horizon | The Economist