The productivity of a developer or data scientist is typically measured by the impact produced per hour invested. While a junior developer may be able to produce linear impact with their hours spent on a task, a senior developer can create exponential impact by mentoring junior team members as explained in From entry level to senior+ developer - Multiply impact with developer leverage.

By taking the time to teach an entry-level colleague, the senior person can not only reduce the development time of the junior, but also impart their knowledge and expertise to the junior. This has the added benefit of reducing the senior person’s own workload, freeing them up to work on tasks that only they can do, while the junior can take care of maintenance or evolution.

Moreover, mentoring helps to spread the senior person’s skills and knowledge throughout the team or organization, creating a more robust and resilient team that can handle complex challenges more effectively. Mentoring can also create a positive feedback loop, where junior team members become more skilled and confident, leading to even greater impact and productivity for the entire team.

In short, mentoring is a highly effective way for senior developers or data scientists to create leverage and have a greater impact beyond their own work. By sharing their expertise with junior team members, they can create exponential impact, reduce their own workload, and contribute to the development of a more skilled and effective team.