Some entrepreneurs start out talking about huge opportunities in this or that area, relying on subjective indicators and personal flair. That is where the mistake lies. Predicting the potential market is a basic step for a successful product, whether it's a digital service or a physical product.
Entering a company into large markets does not give you guaranteed success because there is crazy competition. For example, the industry market for Instagram profile analytics is $78.6 billion, which is a lot of money, and that's assuming your product has some relevance to it. There's a thing called “total target market” but you might want to look at “realistic target market” because those are polar numbers.
The Instagram profile analytics market generates revenue from several sources: in-app ads and app subscriptions. Only small part of profit will go to you because the rest amount will go to pay servers, staff salary, advertising the app, etc. So it's not easy to estimate the actual market size in relation to the potential costs and profits.
In order to estimate the real size of the market in relation to the potential costs and profits is very difficult.
The likelihood of creating an innovative product is extremely low, and finding unique market research would take a lot of time and money. But you can try to do the analysis yourself. There are an incredible number of methods available for independent research. You need to find a couple of tools that work for your company, do the analysis, and find the sweet spot in the numbers.
You're likely to find a number that's as close to reality as you can get. Depending on your business, and the amount of data and skills available, every entrepreneur will have to build a system on their own, because there's no universal panacea for all problems.
If you're an investor, one or two analyses won't be enough as these people are looking for a quick profit and are looking for a good replacement for existing services or products. You have to have a competitive advantage in quality, cost, speed of execution, sales cycles, independence (or dependence) on suppliers, barriers to entry, and more.
When bringing in new people to your product, it's better to leave out the industry metrics and point to other competitive advantages of the company or startup.