This website badly needs editing. There are a lot of bad sounding and awkward sentences.<p>&quot;For several years now, many enterprises and companies employed this architecture in their projects and it almost became the de facto standard therefore it is widely known by most architects, developers and designers.&quot;<p>&quot;Layers don’t have to know about what other layers do, in example: business layer doesn’t have to know how data layer is querying the database, instead business layer expects some data or not at all when it invokes certain method in data layer.&quot;<p>&quot;Some of the features and functionality doesn’t need to go through all the layers&quot;<p>&quot;If you have 20 percent of requests just passes through layers and 80 percent of requests does real processing, it is fine, however if the ratio is different then you are having sinkhole anti-pattern syndrome.&quot;<p>&quot;Event mediator doesn’t do or knows any business logic, it just orchestrates the events.&quot;