How can any modern economy minded person be Marxist?

I have read a good portion of his work and it has a lot of very good ideologies but they all seems to be very Pie in the sky missing the key point of incentive… what is people’s incentive to excel?

Under Marxism all incentive to improve and work hard is removed as all are equal… there is no reward for being better, quicker, or working harder. This is why all communistic style countries fail…

What is a livable wage or how much should a product cost is a very fluid subjective thing…not something to be decided by a bureaucrat.

All the stuff about giving everyone a job, allowing the worker to be the priority commodity, and really removing the cut throat competition driven by greed seems very good and much of it is appealing but it all falls apart due to incentives… the only incentive is to do less…and then watch everything crumble.

Marxism hinges in people’s drive to contribute their equal or designated part

Capitalism hinges on selfishness and the greed of people and leverages that onto providing a superior service to another In order to achieve their greed

I know which one I trust to happen more than another but I’m self taught, is there an angle I’m missing where Marxism doesn’t hinge on people just doing their equal or designated part (and if not Government forces it) ?