Sponsoring and Mentoring

Mentoring is helping another engineer improve through advice and teaching. Sponsorship is giving another engineer a real opportunity, making their work visible to the people who judge it, and sharing the risk if it goes badly. A mentor tells an engineer how to lead a cross-team migration. A sponsor arranges for that engineer to lead one, says so to the director, and defends the choice if the migration slips.

Both matter, but they produce different results. An engineer with only a mentor collects good advice and has few chances to use it