Salaries and short live components make going to space very expensive.
One of the largest expenses are the salaries. Going to space requires the collaboration of specialized teams. But, there are no so many engineers with expertise in rockets and mission systems. So to keep them, organizations have to pay them high salaries.
Some of the materials required are very expensive. And they have a short useful life. For example, the rocket to get to space have different stages. The stages work for a few minutes before they detach and fall. To cost this expense the private industry is working on the concept of the reusable rocket.