+1 to Gary’s post. OTK karts are soft, they bend. But like he said, they can be straightened pretty easily. We’ve done our fair share of tweaking frames back into shape without noticing a difference in performance.
The type of racing and weight does have an effect on how long a kart will last. Something raced at a heavy weight, on softer tires will obviously go through a lot more flexing than a kart driven on harder tires or with a lighter driver.