Is being unpunctual sometimes that bad?

Sometimes I arrive later and well my family and friends already know me like that. I always come if I'm saying I'm coming but not exactly on time.

Yesterday was the 3rd time I came about 15 later to my girlfriend's house. This time she sounded kind of upset. Is being unpunctual sometimes that bad? My life is kind of disorganized and so I might not come on time sometimes.

Is being unpunctual sometimes that bad?
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