You’re asking some great questions, and beyond the fact that there is no teacher as great as experience, it seems tragic how common this experience is, and making great investments is hard even for seasoned professionals. But it’s incredible how often the only two factors used to assess an investment are how much it will make, and how much they like (or know) the people running the deal, when just a few additional questions can often make all the difference.

When looking at a new opportunity, the first thing I do is ask if I believe management’s story. This is really about getting a feel for whether you believe the people running the business or opportunity are qualified to exploit whatever inefficiency they have identified in the marketplace. If they can’t express in simple terms what that opportunity is, why they’re qualified to take advantage of it, and exactly how what they do will generate returns for the investor – run away. This is different than asking if I believe in the management, or like them – it’s about their ability to state in plain language their investment thesis, and back it up with the skills and tools needed to execute.

Next, put it in context - consider the size of the opportunity and this investment’s place in it. Is it a big market, or small? Lots of competition or not? Does this investment bring something new to the space and will gains come from new business or is the plan to take it from existing competitors? If there are no crisp answers to these sizing questions, consider it a big red flag.

The next bit is about understanding the risk of the investment. The single most common mistake made by investors is mis-pricing risk. Markets are pretty efficient, so there has to be a reason someone else isn’t already doing whatever this investment proposes to do and understanding what this dynamic is can be the single difference between good and bad investments. It may be that nobody has thought of it, or no one can do what this will do at the same low cost. Or there is an asymmetry of information, where you know something others in the market don’t yet know. Whatever it is, trying to understand the risk of the investment is key: understanding the timing of the probable returns, appreciating what could go wrong and how management will respond if it does, what change in the environment (like new laws, new competitors, new technology) could turn the deal on its head, and what assumptions need to remain true through the course of the investment. I’m not sure there is any way to get all of the right before making an investment, and surprises always happen, but the more work done to figure this part out can help determine whether the investment is worth making based on what its expected to return, and it often highlights something just plainly wrong with an investment.

Finally, know that there are very few great investment opportunities relative to the number of absolute junk stories out there, and finding ones that make sense for your risk tolerance and timeline just takes work. And experience. And even when you get everything right, sometimes good investments still go bad.