Evil Genius Path: Every great team has one of these. Everyone asks them for advice, they are amazing coders, and they get tons of respect from everyone in management, product, and the trenches of engineering. They are the best of the best, but have NO interest in managing people. They garner tons of soft power over time based on their intimate knowledge of systems and can help steer the product towards its innate strengths. Terminal position: CTO.
People Person Path: Some great engineers are also great managers. Over time, they are recognized for how well the communicate with other teams, and their natural leadership ability. The people they work with would take bullets for them. These engineers eventually realize that they can exert more leverage and add more value by managing a team of engineers instead of writing code themselves. Terminal position: VP Engineering.
Product Path: Some engineers love writing code, but they love making users happy more than they like solving "hard" problems. They tend to be focused on front-end issues, and take extra-special care in that area. These engineers start to realize over time that they care more about what the product does over how it does it. Sometimes these engineers are reviled by their engineering peers because they'd rather "hack it in and try it" instead of making it right. They spend their extra time diving into stats and adding more data collection. They start talking to customers and reading the forums. Eventually, they may realize that they can exert the most leverage by being a customer advocate and designing products instead of building them themselves. Terminal position: VP Product.