What I've found is that the definition and understanding of capitalism varies widely depending on who you ask and what their political persuasions are.
I catch myself defining capitalism as almost anything I don't like about the current world order, while I find my more conservative friends and relatives defining it as if it were a science and an inevitability that the world work the way it does.
I will try to define capitalism. I don't pretend to be neutral entirely, but I see it as important that our organization has a clear standard for what capitalism is so that we can be productive in our struggle against it.
Capitalism is defined by the profit motive. Capitalist countries such as the USA are plagued by individualism. Essentially if I am doing good then that is all that matters regardless of other peoples conditions. The American form of individualism does go hand in hand with nepotism. Rich fathers start dynasties, because they see their children as direct extensions of their own being. This is where the notion of the atomic family comes from. (That is my interpretation.)
The profit motive is dangerous, because there are so many examples where an individual's short term interests are harmful to many other people in society. Individualism fails to take into account the interconnected nature of civilization.
Capitalism is orchestrated through private enterprise. This is what Marx means when he says that we need to seize the means of production, because under a capitalist or feudalist society the critical enterprise of a state is not owned by the people. Instead it is owned by a minority. Whether it be the owning class, the capitalist class, the aristocracy, the oligarchy, etc.
This is crucial because it is imperative that such power over the operation of a state and the lives of so many workers not be controlled by a minority of disconnected elites who have conflicts of interest. This is why in capitalist nations it is observed that basic functions pertaining to the well being of the masses are so severely neglected. Capitalism makes sense when you view the world through the eyes of these elites. They run the world and they make sure that it is a good place for them rather than concerning themselves too much with the fulfillment of people at large.
Under socialism we desire to better implement democracy so that the people have complete control over the functions of the state that pertain to their lives. This means that production belongs to the people and that they operate it democratically and collaboratively.
What about markets? As far as I'm concerned the concept of a market is not exclusively capitalist. Markets have existed for thousands of years.
I do take concern with competition. I would argue that competition is not as productive as capitalist propaganda would suggest for great number of reasons. Consider what competition means in the context of modern American society. It is virtually impossible to survive without having some personal capital and the social safety net in America is laughable. So this means that the competition you are in is actually rather dire. Either compete and win in the job market against your fellow persons or pay heavily.
The capitalist class however know better, because they have already implemented socialism amongst themselves by realizing class solidarity. They understand that they may not always like or agree with each other personally, but they are still united in their desire to oppress those beneath them while upholding their shared affluence.
They run most of the media that Americans consume. They tell us what to think and give us reasons to hate one another.
The capitalists run the state. This is something that some conservatives don't understand. The capitalists control the state and they buy politicians and laws. If they don't like something they buy their way out of it. It has been proven that there is little correlation between what the public desires and what gets legislated and enacted through government.
Power disparities erode our freedoms and capitalism upholds and promotes unjust and unconsentual power disparities.
Capitalism shall also be characterized by market manipulation. Under capitalism the big players consolodate their power and from that position they effecitively orchastrate the market for their benefit. Continuing the cycle of oppression.
Capitalism shall also be characterized by a lack of long term coordination. As we saw in the COVID pandemic, conservative capitalist nations failed to adjust. Sensible socialistic countries were able to plan ahead and prioritize the long term wellbeing of their people and economy over short term interests. For whatever reason America failed to do this as it fails to act sensibly otherwise. Capitalism has proven itself incapable of serving it's people and seemingly even in protecting it's longer term interests. Reasonably you could argue that the pandemic response was the fault of the state. This would require the seperation of capital and the state. In this case it could be assumed that our countries' conservatism is primarily to blame.
Finally I'll add that we don't live in a meritocracy. The scariest implication of capitalism to me is that it allows for the unchecked accumulation of wealth and power on an atomic basis. This is where the term 'you need to spend money to make money' applies. Practically in modern America it is increasingly impossible to break out of poverty if you were born into it and likewise for affluence. What we see is that the rich in this country are essentially sacrificing the lives of many smart and talented people to squander on themselves. This is where it's shown just how inefficient capitalism really is. A society where a lot of wealth is distributed evenly and by consent is one with much more prosperity than one in which that same wealth is spread across the undeserving few.