How are macrophages not beneficial to the human body?

Overall, macrophages are good. However, they also have some pathological effects. 

There is a type of M2 macrophage called the tumor-associated macrophage (TAM) that suppresses the immune system promoting the growth of tumors. Additionally, both types of macrophages, M1 and M2, contribute to the development of atherosclerosis, which can lead to cardiovascular diseases and hypertension.