Scientific studies show that after two years people who had disc surgery and people who did not have surgery have similar outcomes. They have equal amounts of comfort and functional levels.
Certainly, if the patient is functioning reasonably well after two or four weeks of conservative therapy, I think surgery can be avoided.
A large herniated disc causing severe sciatic pain down your leg will prevent normal activities and will require surgery.
Many years ago, I herniated my disc Saturday evening and had surgery Wednesday evening since I had almost no right leg function and could not stand for more than 30 seconds. Clearly, those kinds of severe symptoms require surgery to avoid a very long recovery time and probable permanent weakness.
Remember, the major pain from a herniated disc is sciatica down one leg, not low back pain.