There are many stories why the Omega Beta21 "Pupitre" has its crown on the left, as the Bulova Beta21 "Alienhead" has as well. The most famous: as it is just a setting- and not a winding-crown and it is the most precise Swiss watch ever made, it is never needed and could be placed at the left side of the massive case. So, but why not make it look more like a ordinary watch? And when you look at the movement, then serious doubts about this explanation arise quickly. Remember, the first versions of the Beta21 needed the 357/303 batteries and these were obviously the thickest part of the movement. Now, and this battery was placed on the bottom of the movement -- a mistake obviously when you want to shape the case along the different height-levels to make it a bit thinner. Why a mistake? Because when the thick battery is at the bottom of the movement, then the shape of the watch and the dial bows away from the wearer and not towards the wearer. To solve this Omega & Bulova simply turned around the movement: the thick part is now in the top area of the movement making the watch taper and bent towards the wearer: like a pupitre; like a desk. Nice, but the crown is now on the left side. So, here we have an obvious case of horlogy-folklore that was romantically used to hide a design-mistake. Myth Busted: #HorologyMythBuster.
The reason for this mistake? The pressure from far east during the race to the first quartz-watch.