Depends on the nature of the ball, the usage, the user, the conditions, and the maintenance of the ball.
I have had balls last for years and balls that lasted for less than 30 games.
The most important factor is maintenance. Unless a ball is a defective dud, properly maintained it will last for at least a year at minimum, possibly for several seasons depending on the use. Keeping the oil out of a modern ball is getting a little more difficult as the absorbtion rates incease, but it is possible.
Clean the ball after EVERY set with a good BOWLING BALL SPECIFIC cleaner to keep the absorbed oil to a minimum. Touch up surface as needed, Hot water bath every 12 games or so.
For the love of bowling, NEVER stick your bowling balls in the oven!!!
A few short hot water baths will do the trick, if you think its not enough, take them to your local shop to be revived or rejuvinated.
The other factor is use. If the ball is your benchmark and you almost always throw it, it will eventually die, and likely before anything else in your bag. I cannot tell you when that will be...could be 30 games, could be 300, could more.
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"...do or do not, there is no try."
St. Louis USBC Sport Bowling
Best Bowling Pro Shops Inc., St. Louis MO.
