Generally speaking, the pre-sales engineer is the person who provides technical support in the sales of scientific and technological products. During the sales period, the sales engineer acts as an encyclopedia of the sales team, answering specific customer's questions from technical solutions. They master the process of product demonstration and give technical demonstration of products.
Pre-sales engineers and sales staff work together to sell the company's products, services and solutions. When the products to be sold are complex or highly technical, pre-sales engineers are needed. Pre-sales engineers are essentially solution experts.
Sales people ensure the funds (where the budget is and how to get the budget approval), while pre-sales engineers focus on winning the technology purchase (proving that the solution is the best for the buyer).
The product manager is the person who controls the direction of the product. By listening to the voice of the market, he explored the market demand, expounded the product positioning, and made clear the process of bringing products to the market.
A pre-sales engineer is a product consultant (solution expert) who supports a single salesperson. He supports the sales process of scientific and technological products through technology and industry experience, and persuades customers to buy and start the project in the early stage of the project.
Usually, sales staff will ask the product manager for sales support because there are not enough pre-sales engineers. In the absence of pre-sales engineers, product managers must be brought into sales. With a well-trained and well-staffed team of pre-sales engineers, product managers do not need to make sales calls or make product demonstrations.
Most pre-sales engineers have technical background, but some excellent pre-sales engineers have no technical background. This usually depends on what the industry is like. If it is a mature solution and customers prefer business people, then pre-sales engineers are more like solution experts and often do not need technology.