On the technical solution level the weight+discard solution is much more reliable. (let's ignore the stupidity that the expensive solution stops the production line. In the real world it would just blow out the wrong ones using compressed air) They have logs from the machine for auditing purposes. They have a very simple to understand knob (the threshold weight) and they can use that to adjust the system to changes in their product. The fan has none of this. If an empty box goes through nobody will know what to change. Maybe the conveyor was a bit stickier that day? Maybe someone set the fan to the lower speed? How to adjust the fan setup when we are making packs of tiny tubes for a hotel?
That's one level of reliability. The other is the organisational reliability. The CEO has the empty box problem. He wants it solved. He can commission an engineering firm who comes up with a solution. It will cost a pretty penny, but if the CEO is worth his salt he can write in performance requirements in the contract. They know they will get a working solution. Alternatively the CEO can go down to the line, he talks with the people there, he tells them about the problem. He offers an incentive for the solution. Let's say $2k. Someone proposes the fan solution, someone proposes to tune the filing machine more, someone proposes to measure the pallet of boxes with the forklift before shipping. How will the CEO know which one to pick? All solutions sounds very reasonable to him. Even after they picked one solution, how does he know it is working as intended? Who does he go to complain when a defect slips through?
On two levels.
On the technical solution level the weight+discard solution is much more reliable. (let's ignore the stupidity that the expensive solution stops the production line. In the real world it would just blow out the wrong ones using compressed air) They have logs from the machine for auditing purposes. They have a very simple to understand knob (the threshold weight) and they can use that to adjust the system to changes in their product. The fan has none of this. If an empty box goes through nobody will know what to change. Maybe the conveyor was a bit stickier that day? Maybe someone set the fan to the lower speed? How to adjust the fan setup when we are making packs of tiny tubes for a hotel?
That's one level of reliability. The other is the organisational reliability. The CEO has the empty box problem. He wants it solved. He can commission an engineering firm who comes up with a solution. It will cost a pretty penny, but if the CEO is worth his salt he can write in performance requirements in the contract. They know they will get a working solution. Alternatively the CEO can go down to the line, he talks with the people there, he tells them about the problem. He offers an incentive for the solution. Let's say $2k. Someone proposes the fan solution, someone proposes to tune the filing machine more, someone proposes to measure the pallet of boxes with the forklift before shipping. How will the CEO know which one to pick? All solutions sounds very reasonable to him. Even after they picked one solution, how does he know it is working as intended? Who does he go to complain when a defect slips through?