It is the best because of its simplicity and easy to use.
Although there are many Visio alternatives for Mac such ConceptDraw, LucidChart, SmartDraw, or OmniGraffle according to my opinion they can not replace Visio. Since I work as a network administrator, Microsoft Visio is very important for me to draw network diagram / topology. Although Microsoft has been officially releasing Microsoft Office (e.g Word, Excel, PowerPoint) for Mac, Microsoft still does not release Visio for Mac, at least until now.
One program that missing when using MacBook is there is no Microsoft Visio for Mac. This article is written intended to guide you how to Install Microsoft Visio Mac / MacBook Pro / MacBook Air running OS X El Capitan.