English to Italian Tech/Engineering Automation & Robotics lawnmower robots

I understand the parts are replaceable, however, because I worked as an engineer, I also know that parts go obsolete. When a part goes obsolete, the company has three choices, replace it with an equivalent part, redesign it to use a slightly different part or make a "life time buy". The first two choices require engineering design time and some amount of money. All parts have to be evaluated and tested, even if they are equivalent. A complete unit using the new part(s) may also have to go through safety testing again. The third choice takes a whole bundle of money to buy a lot of parts and put them on the shelf.

si sta parlando di parti di ricambio per un robot. l afrase è tra virgolette anche nel testo,

grazie