Be a fan of GUNS in general, don't get sucked into "X" is better than "Y", understand that each make and model may have attributes that suit others while not suiting you. Be able to look past your own nose and see things from the perspective of others. Every now and then try something new, if you're a Glock fanatic, go rent a Sig for a couple of hours. If all you've ever carried is a steel "X" try something from the polymer side of the house.
Understand that every make and model is capable of failure, no design is perfect, and sometimes it IS the gun that's messed up and not the shooter.
Variety IS the spice of life and you never know what you might like till you try it.