medical industry... use it once and throw it away.

You could be, but it is unlikely.

Reimbursement is based on the DRG (diagnosis-related group). For example, this instrument can be used for removing a gall bladder, possibly the most common minimally evasive procedure. The hospital/physician gets reimbursed on the procedure (the DRG), not what they used in the procedure.

As for sterilization, disposables like this are generally sold on cost. The reusable instrument has a higher up front cost plus the cost of sterilization. Amortisize that cost and you are likely to find the disposable is cheaper. Cheaper is much more important in healthcare these days than green.

Also, there is a higher risk with complicated instruments like this for not getting fully sterilized and infection can easily cost in the upper 5 figures, low six figures. Combine that with a growing list of never-events (“complications” in the hospital that should never happen) that don’t get reimbursement, disposables are even more attractive. For example, the disposable company may have clinical data showing infection rates are lower with their instrument over the reusable instrument. The hospital may have to pay for a patient’s infection.

As for solutions, make the disposable as lean and mean as possible. Durability is a small issue. Use materials and manufacturing processes that have a smaller footprint. Use clinical data to show using the disposable has better outcomes and uses less materials in the long run (the amount of time, materials and energy to fight a blood stream infection is staggering).