Statistically I believe that's true, but not always. Just figure it will probably be faster, but don't assume something's wrong if that's not the way it goes.
First baby, I started feeling contractions about midnight, to 1am. Called dh to come home at 2am, tried to sleep. Contractions didn't get serious until that evening, 7pm contractions were really hard, we went to birth center... I was dilated to a 3, had baby at 11pm.
Baby #2, went to regular appointment, 10-11am ish, not feeling any contractions, she checked I was dilated to a 3. Talk about different! Baby was born around 6am next morning I think?
Common factor was both were born 10-15 min after my water broke.
Baby #3, my water broke on it's own, I freaked out expecting to give birth in the next 15 min. Gave birth 26 hours later. Didn't get any good contractions going until about 4 hrs before birth.