Your comment hits the nail on the head here.<p>Standard statistical tests used in a&#x2F;b testing are based on one check. If someone is checking repeatedly on a test until they get a &#x27;significant&#x27; result, your chance of getting a getting a false positive is many X the stated significance.<p>Best practice - set a pre-defined end, and one or two defined early check-in points where only make an early call if result is overwhelmingly significant or if the business has fallen off a cliff.