The short answer
A hair oil and a conditioner fill different roles. Choose a finishing oil for your styling priorities, and follow the specific product directions rather than treating it as a replacement for your conditioning routine.
Name the finishing goal
Shine, softness, definition, and hold are different goals. Pick the one that matters most to you. A product aimed at a polished finish is a different purchase from one designed to hold a style in place.
Match the format to your hair
Consider hair texture and the products you already enjoy. A richer routine may suit one person and feel excessive to another. The official OI Oil page particularly highlights coarse or dry hair, which makes it a useful starting point for that shortlist.
Keep the buying choice specific
Check the current directions and size before ordering. Our OI Oil review focuses on buyer fit and routine role so you can decide whether a finishing oil fills a real gap.