Most companies I’ve invested in have been ones that I wasn’t previously familiar with. I only became familiar with the product and industry after many hours of research. This isn’t on purpose—just a result of me not being a user of most public company’s products. The advantage of this is that I approach learning about these new products from a clean slate with few biases. The drawback is that I will probably never understand the product as well as I would if I was a regular user.
The opposite of this is Peter Lynch’s investing style: “Invest in what you know.” Lynch advised people to invest in companies they know and love. Logically, this makes a lot of sense, but I’m not convinced this method is any better (or worse). The advantage of Lynch’s approach is that a user might have a unique insight into the value of a company that other investors may not have or appreciate. The drawback is the user will almost certainly overemphasize their own experience with the company and may discount what the greater population thinks (i.e. the base rate).