Slipped

He slipped the key into the lock and turned it quietly.

The building's safety standards have slipped over the years due to lack of maintenance.

She slipped and made an error in her calculations, resulting in an incorrect answer.

The quality of the hotel has slipped since the new management took over.

The package slipped from the delivery driver's hands and tumbled down the steps.

The airline's punctuality slipped due to bad weather.

His physical condition slipped after he stopped exercising.