The job really requires the ability to forge connections with other human beings and to engage them in a way to sell products; I don't think a bachelors degree is required. Probably the only technical requirements for a sales employee are the ability to use a CRM (customer relationship management) system (like Salesforce), some Microsoft Office features, some basic knowledge to do an inventory search based on entering the SKU into a computer, and so on. The average sales employee at a boutique doesn't even need to use Excel. The position of a sales employee is highly compartmentalized and specialized because retail sales employees have a relatively short life, some are even seasonal, it's unusual to see a retail sales employee (even in the luxury space) last longer than 10 months. Retail employees as a whole (including non-luxury) have a 60% turnover rate every year! That means more than half of the staff changes every year!
There is usually an "office manager" who handles shipping/receiving, inventory audits, etc. that person needs to know the computer programs, the UPS/FedEx account programs, and insurance requirements (certain packages over a certain threshold need different insurance protection).
The General Manager is basically a people manager who can tie the team together and who can generate sales as well; the GM needs to create meaningful events, some general managers will need to do some PR work and build relationships with newspapers and magazine advertising execs, build relationships with clients and other business vendors, handle problems, keep a budget, etc.
I'm not belittle-ing a sales employee at the boutique, let me be clear of that. My first job ever was in retail sales, so I've been there, and I learned a lot about consumer psychology; I wouldn't trade my experience for the world. While working in retail sales I've met individuals who were; one was a former school teacher, one with an MBA, some employees whom were independently wealthy and had a passion to work with public consumers, one with no degree but who was an incredible individual who knew exactly what to say at the right time. There is definitely a lot of talent in the sales industry. The better retail sales employees take good notes (anniversary, children's birthdays, your birthday, your wife's birthday, etc.) so they can celebrate life's milestones with you. They track your preferences (vegetarian, gluten free, allergic to nuts) so future events are safe. Once these dates and preferences are programmed into the Salesforce computer, the Salesforce computer gives the employee birthday reminders, etc. This is all part of the job, to build relationships with clients. However, most retail sales employees don't even do their job, instead of writing Christmas cards, they just let the Customer Relationship Management software send generic "Merry Christmas" emails, forgetting that the recipient is of a religion that doesn't celebrate Christmas.