This statistic is unofficial and is used by analysts to easily count the number of long drives a team has. Since each play can take a maximum of 40 seconds, a ten play drive will always take at least 1/3 of a quarter to complete. More often than not, a ten play drive will result in a scoring opportunity.
A team with a lot of ten play drives is most likely winning games and playing very well. Time of possession is one of the key stats used in picking winners, so knowing how often a team goes on ten play drives is helpful in making the correct pick. The selection of 10 plays as a point to mark is arbitrary, and chosen because it is an easy, round number, and a multiple of 5 (five play drives are also counted by analysts). A ten play drive may contain any combination of 1st, 2nd, 3rd, or 4th downs.