Make it as difficult as possible for a criminal to gain access to your pockets. Then, when the plane lands and they get up to leave, their bags are gone. Limit the amount of carry-on luggage. Place it beneath your seat and within your sight or in the overhead bin directly above. And that usually involves going down an escalator.
Crooks love crowds.
They prefer to operate in places of transition. So this is a popular working area for thieves. So is the baggage claim area. Thieves are known to loiter in these locations and take unattended property if not claimed right away. Many airports no longer have security guards, because it's an extra expense.