Owning a “real” business means you need to think about bank loans or financing, leases, maintaining inventory, business insurance, finding staff, training staff, etc. You then need to factor in finding a prime location for your business. If you don't have enough footfall then you can expect to be shutting up shop in as little as a few months. In fact, 50% of small brick-and-mortar businesses fail within their first 3 years.
The cornerstone of your affiliate business is about setting up a website that's focused on a specific niche. You research low competition keywords for that niche, with the aim of ranking on page one of Google for those keywords. People visiting your site then click on a referral link, and if they make a purchase at the destination store, then you get paid a commission. That's why some people call it “referral marketing”.
Usability testing is a technique used to evaluate a product by letting users try its features for free and record the process while doing it. This usability exercise gives direct information on how real users use a system and shows if its features are user-friendly or perhaps need some work. This type of testing can be used to assess features of websites, apps or various devices.