You jump I jump, but I landed on hospital bed

"Uncle, why do you come to hospital"
 "My leg is painful, doc"
 "What happen?"
 "I think I broke my leg"
 "Huh, road traffic accident? Hit and run?" I asked anxiously as these are police case. My heart rate and breathing increased as police case means the court could subpoena me to testify one day, which could be years later.(Of which i will try to remember what happen today)
 "No, doc, I tried to jump over monsoon drain" answer a middle age gentleman in softest possible way. "You what ???!!!"
 Wow, we have a guy who tried to jump over monsoon drain, and landed on hospital bed instead.

 This is a typical monsoon drain found in my country

I do not get it. Why on earth he wanted to jump over monsoon drain. I tried to come with best possible reason:
1. Accident happens all the time, all the time accident happens
 2. He tried to pick up something in the monsoon drain
3. Someone is swimming or drowning, and he intended to help

 To get the best answer,I even asked PhD Google and found out that:

 1. Car can be in monsoon drain

2. Not just car, we see bus as well

Conclusion: Man can be in monsoon drain as well The million dollar question is : WHY ??

 It all started when he and his friends decided to jump together (Keyword here: together). He trusted his friend will jump. His friend did indeed jump with him, but they all made it to the OTHER SIDE. So instead going to the other side together, he was sent to hospital.

 Moral of the story: Do not ever jump over monsoon drain. Is for car and bus.