Socialism implies a lot more centralization than capitalism.
The answer is, like always, included in the question.
While socialism is to be ‘implemented’ – by a ‘central figure’, capitalism is an environment. A place where the deciding agents – the entrepreneurs, ‘make it happen’.
Hence socialism – which is a ‘thing’, to be implemented, not an environment for entrepreneurs to roam ‘free’ – will eventually fail. No matter how well intended the implementor, nor how hard it tries to make it happen.
In capitalism, only the entrepreneurs might fail. When the market is no longer free – oligo or mono poly, the situation closely resembles a socialist one. Things go south. Because the decision making agents are too few and far apart – no longer able to cover all corners, just as their socialist counterparts.
Comparing socialism with capitalism is like pitting an apple against agriculture.
An apple, all apples, will eventually become rotten. No matter how hard one might try to preserve it.
Agriculture, on the other hand, will yield according to the available resources and the effort put in by those involved in it.
https://www.quora.com/If-Socialism-has-always-been-poorly-implemented-why-wasnt-Capitalism