As a side note about this type of set trigger so people will understand exactly what this trigger is.
It is a "single phase" or "single lever, double set" trigger. The "double set" refers to there being two "triggers". The "single lever" refers to the fact that only the rear trigger has a blade on it to contact and release the lock sear.
The rear trigger blade constantly places a pressure against the sear arm to keep the nose of the sear away from the half cock and full cock notch unless the trigger is "set". Because of this, the rear trigger must first be set before the lock can be cocked or placed in the half cock position.
The front trigger cannot fire the gun unless the rear trigger is first set.
The reason for these triggers to exist is, they can be used with any lock. Even locks that don't have a fly in the tumbler.
They are popular with target shooters who don't mind having to set the trigger before they cock the gun but as chuck-ia says, they are not popular with hunters.