time and time again

ADVERB
19 LETTERS · STARTS WITH T

time and time again is a valid 19-letter word worth 22 points in Scrabble and 27 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS
T1I1M3E1A1N1D2T1I1M3E1A1G2A1I1N1
1 + 1 + 3 + 1 + 0 + 1 + 1 + 2 + 0 + 1 + 1 + 3 + 1 + 0 + 1 + 2 + 1 + 1 + 1 =22 PTS
DOUBLE WORD → 44TRIPLE WORD → 66
MEANING

What does time and time again mean?