You’re not going to change the world by building a sales force, even if you build the equivalent of Napoleon’s Army to sell your products.
If the most exciting thing in your business plan is the number of sales reps you hope to hire once you get serious funding, you are not likely to get the funding.
If a company is fundable (not merely viable) your sales force will manage the demand for your products as your company flies through the tornado. The tornado doesn’t wait for the presence of your sales force to materialize.
This is what Marc Andreessen means when he starts talking about how the goal of any seed stage company is to find the right “product/market fit.”
The most exciting part of your business plan is the potential for you to change the world by finding a new “whole product” that everybody wants, but that only you have built. If the most exciting part of your business plan is something else, your plan is probably not very exciting.