coolant hose clamps

Sorry, not oetiker clamps, spring clamps

Steven, clamps of all types on "rubber" hoses (fuel/oil/coolant) are there for security ie to stop the hose slipping off the spigot.

So good hose fit to prevent leaking, clamp to retain hose in position.

If your clamps are not performing as described - replace them.

Unless you damage them taking them off then they are reusable. Placement is a key factor in preventing leaks. I place them up by the flared end on the metal tubing. This will increase the pressure point it exerts. Do not place the clamp on top of the flared edge on the fitting. Just behind it. I see many place the spring clamp way back at the cut hose edge and sometimes this allows the hose to leak. You can feel the flared part of the fitting with your finger and slide the spring clamp up next to it. I've never had one leak doing it this way.

If you twist or over squeeze the spring clamp and damage it  then replace it.