Why high slippage tolerance can worsen sandwich losses

High slippage tolerance is permission to accept a worse execution result. It is not an extra fee that buys protection or a guaranteed requirement for a successful trade.

Read the amount bound

Hypothetical example: a quote expects 1,000 output units. A minimum of 990 rejects execution below that level; a minimum of 900 permits a much larger reduction. The second transaction authorizes a worse outcome even if the interface initially displays the same expected output.

Ethereum’s MEV explanation describes sandwich-related execution harm. Wider acceptance can create more room for adverse ordering, though not every difference between quote and execution is an attack.

Do not use tolerance to hide another problem

A shallow pool, large price impact, transfer tax and stale quote are different causes of poor output. Increasing tolerance does not deepen liquidity, remove tax or make a malicious token sellable.

If a token requires unusually broad tolerance, inspect its documented deductions and route compatibility. Consider whether the resulting minimum is acceptable at all.

Balance protection and failure risk

An extremely tight limit can lead to more reverts when state changes before inclusion, which may cost gas. A wider limit trades some of that failure risk for acceptance of worse execution. Choose deliberately based on the outcome you accept, not a universal percentage from a forum.

Where supported, private submission can complement sensible bounds. It should not be used as a reason to remove those bounds or ignore its own coverage and trust assumptions.