Der Haushalt ist für ihn aber nicht so wichtig. Wenn er keine Zeit hat, bleibt der Abwasch schon mal liegen.
Source: "Direkt", LektorKlett, a story about a boy who lives alone
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Sign up to join this communityDer Haushalt ist für ihn aber nicht so wichtig. Wenn er keine Zeit hat, bleibt der Abwasch schon mal liegen.
Source: "Direkt", LektorKlett, a story about a boy who lives alone
He doesn't take care of the washing-up immediately, leaving the dirty dishes (in the sink, we may presume) for now, putting it off.
Das kann schon [ein]mal vorkommen.
is a colloquial way of expressing that something may happen once in a while. It also implies a certain carelessness and/or fatalistic attitude in respect to the event and its consequences. How frequent exactly this "occasional" event is expected to happen depends on context - from the wording in your example, I'd guess you shouldn't be overly surprised to find dirty dishes in/around the sink more often than not.
Your confusion with the translation as "ever" you found in the dictionary comes from a different use case:
Hast du das schon [ein]mal erlebt.
is a way of asking if you have ever(literally "once") experienced this before.
Additionally, in Germany, we often use "bleibt der Abwasch schon mal liegen." not only for dishes. Sometimes, "bleibt der Abwasch schon mal liegen." is a general sentence to tell, that we dont have time to keep the house clean.