This is the most common web writing mistake made by web designers. Brochures and print marketing materials use sales language that does not scan well on a website. Any use of sales language on a website beyond the usual “order our products here” stuff will make your users click off faster than a Guitar Hero champion can shred the final level. Ditto with puffed up marketing claims such as being “the best” or “the greatest”. Brochures are riddled with this stuff as countless marketing studies have shown that such language does work in print marketing materials.