1. The economy was bad
2. The leadership quality was garbage
3. The leadership experienced no negative incentives for bad performance
1. and 2. are quite natural properties of Classical Leninism, which emphasizes socialism in regards to economic matters and the promotion of the working class and ideological dogmatists in matters of government. Though the Soviet economy did experience substantial economic convergence with the West from the end of the Civil War to the mid-1970s, and, due to 2. and 3., it clearly could have squeezed out a few more points of convergence with the imperialist countries, it is very clear the Classical Leninist system has inherent disadvantages over capitalism. 2. and 3. also resulted in the influx of antileninist subversive elements into the sinews of the polity, which ultimately resulted in its destruction politically as well as economically.
America currently experiences 2. and, despite elections being more competitive than ever before in its history, 3. So far, it does not experience 1, which saves it from being discredited from a purely economic standpoint, though by no means saves it from political collapse. Individual parts of the American system may experience penalties for bad performance, but the leadership structure as a whole never does, as the electoral penalty is usually over only one axis of bad performance. The competition is also, quite often, literally over if a person with a red or a blue colored hat, who differ with each other on about 1% of the policies they could realistically diverge on, gets to implement the exact same stupid policy in exactly the same fashion. Even primaries totally fail at producing competent leadership, due to ability to please the crowd being at best imperfectly correlated with ability to competently govern. Consider Cuomo. Also, term limits and powerful incumbency advantage, both de facto and de jure, make it impossible for there to be any political advantage in doing a good job relative to doing a bad job. Thus, no state governor except Steve Bullock so much as bothered to contain the coronavirus. Western-style democracy, as well as the current sovereign democratic Russian system, have failed. Chinese Communism has, so far, succeeded. It is, of course, essential for the thriving of the Chinese economy that the party’s control be laxened in certain areas, but, so far, the leadership has prioritized the economy over the extent of its reach, and has sought to find ways to ensure that there is no contradiction between the two goals.
How do we ensure the economy is good? Select the best economic policies. The economy is a machine for producing goods and services; finding ways to maximize output is relatively straightforward.
How do we ensure the leadership quality is good? Make the sovereign body (in the United States, the sovereign body is the overly large and unwieldy Congress, which should clearly be much smaller if it is to have impact) run by a council of superforecasters, who all believe exactly the same things and deviate from their understanding of future reality neither to the right nor to the left, which should make resolutions of questions of values much easier.
These superforecasters should freely design incentives for bad performance not just for themselves, but for all levels of society. They should understand the public will is quite malleable and hard to determine, so it is best not to rely too much on that thin reed.