[brunolazzaro]

I think it boils down to this 3 things:

1. Salary. Your pay will be less than the one of a Senior Developer.

2. Role and tasks. You will, as a junior developer, be taking on tasks better suited for your relatively "non ripe" skills. This doesn't mean that you'll get the short end of the stick. It means that you'll be assinged tasks that fit your current skillset.

3. Experience. While you might be a top-notch developer, you don't have "real-life" experience. Most of the times senior developers have years if not decades of experience on their backs. And with time comes wisdom.

These three things combined are a compelling reason to hire Junior devs for small tasks and projects.