To cover all the bases is to prepare for every possibility. Make sure we cover all the bases.
It comes from baseball, where every base must be guarded at once. It means completeness rather than depth, so covering all the bases can still be shallow.
1phrasecover all the basesTo prepare for every possibility.
“Two extra clauses were added to cover all the bases.”
cover all the bases is a phrase.
cover one's bases comes from the rules of baseball, where the defending team needs to assign an infielder to each of the three outward-facing bases.
Etymology from Wiktionary, CC BY-SA
Practised in Idioms