كيف تحافظ على مصابيح الشوارع LED?

Sometimes I see very dim HPS street lights. Are they going to break down?

It is really strange that there are always some of the street lights going off, and every time not the same one. Why does this happen?

I heard that low pressure sodium lamps are cheap, but it seems that in USA and Canada, most of the street lights are high pressure sodium lamps. What are the weakness of the low pressure sodium lamps?