Why does it take 10 hours to fly gatwick to dubai but only six hours dubai to gatwick?

My flight to japan stops at dubai. the flight details show 10 hours to dubai, but only 6 hours back from dubai
Answer
The flying time (# of hours travelled by the plane) is actually the same. the details indicated are local timings (departure time in dubai - arrival time in gatwick and vice versa), hence the difference.