Or when we are seeking answers to overly tough questions. Many times a spirit guide will assist you when you are experiencing trauma - be it physical or emotional. Other times you will notice subtle nudges, like a tap on the shoulder to alter your course. Some people need their assistance - at all times. Some people may never require spiritual assistance from a spiritual guide at all.
Some people can, and do, rely only on their higher self.
And the higher self is a spiritual guide. I've witnessed several apparitions in my day. Our second-story room was directly over the main area of the Pub. One night while trying to sleep, after an eventful sight-seeing excursion to London, Lesley and I were talking in our overly dark bedroom. We were both facing the hallway - and it too was pitch black.