When people come to me seeking my advice because they think I'm an expert in my field, I try my hardest not to let them down, and I give the best advice I can give. When people seem satisfied, I start to wonder whether it was wise of them to trust me because nobody knows my own imperfections as well as I do, but whether it is because of trust or image, there is a myth commonly held of the expert. This is why physicians are held in high regard and are respected. They are seen as experts in health. I am not the only one who feels this insecurity, and indeed there is a term for it: impostor syndrome.
When I start to doubt the veracity of my own advice and expertise, naturally I start to question the veracity of other people's advice and expertise, and certainly being sceptical of expertise can save us, e.g. the Commonwealth Bank financial planning scandal.
But at the same time, I understand the comfort of deferring to expertise. Before I went to the gym, every second person I met gave me advice on health and fitness. They'd tell me to buy a bike and then go into detail about different types of bikes, materials used for the types of bikes, and so forth, and yet others say different things, e.g. I should be playing soccer or tennis or badminton. Of course, deep down I knew that these people simply tried to sway me one way or another based on their own personal interests. If they were passionate about cycling, they'd naturally want to steer me towards cycling with them.
After I joined the gym and received advice from one fitness consultant, my friends stopped giving me amateur advice. When people asked me what I did for health and fitness and I told them that I was now a gym member and that my fitness consultant or personal trainer prescribed me this and that, that weight of expertise seemed to intimidate other people from giving me their half-baked views, and suddenly I feel calm and at peace because I don't need to listen to diverse viewpoints, evaluate, decide for myself, and feel ashamed if I made the wrong choice. I can just obey the expert, and typically no one dares to question the expert.
If I knew more about health, maybe I'd do my own research, but health is not my area of expertise, nor is it an area I am passionate about, so I am satisfied with deferring to the experts in this area. But in other areas, e.g. personal finance, I am quite passionate about finance and prefer to do things myself rather than rely on a financial advisor or financial planner, and given the bad reputation financial planners have had recently, I am glad I've taken this route.
There is probably no best way to handle uncertainty. In some areas you want to do it yourself and in some areas you want to outsource to an expert.