The quickest method for a thief to open your safe is with the key, combination, or access code.
If you opt for a key lock safe, you may not want to keep the key so close to where your safe is. Burglars will anticipate that. Instead, keep it in a discreet location or container that people won't think to look in.
For safe combinations, it's better to memorise them than to write them down. If you must have a copy of the combination, give it to a trusted friend or family member.