If you take the 'each according to their abilities' and 'each according to their need' the primary function of communism attempts to fulfill the each according to it's need side of things, while also portraying the 'ability side' will have to do less work than in capitalistic systems.

The problem often arises that the social distribution system disconnects from the ability to produce.

There are claims like this:
"By adopting this pattern the work keeps getting done while nobody is denied what they want."

The assumption is that everyone gets what they want, if they just work.

This is why I often think of communism as being sold on the 'needs' basis, but will always disconnect and not provide on the 'abilities' basis.

The wants of man are infinite, but the abilities of man are limited. That's just a fact that can't be reconciled.

That the terms 'wants' instead of 'needs' is the most used way of selling the ideology is a indication that there will be problems down the line.

later in the model you hear:
"Supply will limit demand somewhat"

which runs counter to providing everything that people want

Also:
"But, the world only needs so many shoes and iphones."
Which again shows that there is no objectivity that people will get all they want, but will be apportioned a limited ration of what is deemed as socially acceptable.

What often happens between anarcho-capitalists, and anarcho-communists, is they will see the problems in economics in a similar fashion, but when they go to reach for a solution the solutions are inverse.

Ancoms will want a singular all encompassing social construct to fix the problem. Ancaps will want complete absence or the very least amount of social constructs with the most amount of individual sovereignty.

This is what makes the two polar opposites (in my way of seeing it).

The other thing about the social construct of ancoms is that it does require a social construct which in turn requires investment of authority.

Once the authority is invested in the construct, the only thing keeping the construct from being coercive, is 'the right kind of people' leading the construct. So any drift of the leadership to authoritarianism is not backstopped by anything other than mass defection, which collapses the construct, leading to eventual poverty until some other quasi system can be adopted.

The advantage of the ancaps model is there is no need to build a social construct and invest authority. It can be fully decentralized.