Using 'swear off' shows a strong commitment to stop a habit, often more emotional than a simple decision.

Strong Commitment

'Swear off' often implies a permanent change, though in reality people might not always follow through.

Emphasis on Permanence

Often, a personal negative experience leads to the decision to 'swear off' something.

The phrase is often used after a negative experience with something, not just a simple dislike.

Despite the intent, 'swear off' doesn't always mean forever; people may return to what they've forsworn.

'Swear off' can indicate an emotional, spontaneous decision rather than a well-considered plan.