Charities run differently from businesses because they are different. Charities provide services to people who cannot pay for those services. Businesses avoid this work.
What is desirable in one world is often foolhardy in the other.
These four common financial constraints, for example, are like a rorschach test for organizations. A charity sees the situation and thinks, "We have to act!" A business sees these constraints and thinks, "We have to get out of here!" Both are right, in their own way.
Four reasons your charity doesn't run like a business
1 - The people you serve can't afford to pay
This is probably the most classic example of "charity". Someone needs something, usually basic and fundamental for their well-being like food or shelter, but they can't afford to pay for it.
2 - No one can afford the service
Sometimes the thing people need cost an enormous amount of money. Often it takes years to try to invent or build that thing. Sometimes it seems impossible to create the thing. There are huge amounts of money, time, and risk involved, like finding a cure for a deadly disease. We can pool funds from a lot of sources to get the work done, but the time and cost involved mean that the donors rarely benefit personally. They really are funding it for others' benefit.
3 - You're providing a service people can't know they need
There are legitimate reasons why people who need your service might not know they need it*. One of the most common reasons is that they are part of a future generation. Or maybe a crisis arose suddenly and requires immediate action. If you wait for beneficiaries to understand the need and agree to pay, it will be too late to actually do anything. This is often the case for environmental protection and climate action.
4 - The people you serve shouldn't pay
Sometimes it is just flat-out wrong to expect the person who benefits from a service to pay for it. Charging them money would undermine the entire purpose of the work. Reparations and reconciliation programs fall into this category, as do crisis hotlines.
Why does this matter?
The better you understand the constraints facing your particular project or organization, the easier it is to craft a strategy to get the work done.
And remember that things are always changing. What was once impossibly expensive may become affordable. Government might take over a charitable service. The private sector might exit a market and leave an enormous gap.
We have to understand and respect the rules of our worlds if we are to thrive.
* Tread lightly here. The charity sector has a bad habit of assuming people need "help" because of their race, culture, low-income status, or geography. That mindset creates and perpetuates injustice, it doesn't solve it.