It's not okay to be careless with things.
Brett, who has trouble keeping track of things, just got an expensive new phone and is outside at the park playing with it.
Brett wants to take a quick walk.
Brett puts the phone in his pocket and walks around the park, then sits back down.
Brett puts his phone down on a bench and takes a quick lap around the park for exercise.
Brett keeps his phone while getting his exercise and enjoys the phone for a long time to come.
Someone else sees the phone and takes it, and Brett is dejected that he lost his phone.