The world changed almost completely when concrete was first invented because of the fact that it allowed us to create structures that were incredibly durable and it did not have the fire associated dangers that come about when would is used either. Making a house out of stone used to be impossible until bricks were invented, but suffice it to say that concrete took this structural integrity to a whole new level at the end of the day.
That said, while concrete might seem like a more or less completely unassailable and indestructible substance, suffice it to say that it is something that can be damaged in more ways than you might know about right now. That’s why you need to be careful with it while cleaning it, but you should know that the best pressure washing techniques don’t really allow such damage to be inflicted. It’s all about knowing what the right angle to aim your pressure washer with happens to be. This angle can be your main source of focus because getting it down pat will help you avoid the notorious concrete damage that improper pressure washing can send in your general direction.
To answer the question that you are fretting over, pressure washing is not bad for concrete at all. It has the potential to be bad if not done properly, but trained experts are already aware of the pitfalls of not doing their job right. Using a lower pressure setting or soft washing lets you clean any concrete surfaces in your house without wearing away at them, thereby making your house look nicer from the outside and protecting your car from surprising bumps and jolts.