When you buy Modular Kitchen, company gives warranty for the hardware equipments. If there is designer or contractor who is making your modular kitchen, he will inform you about available warranty. If you buy from Modular Kitchen showroom, shopkeeper will forward it to you.
In long run, if you are doing proper cleaning & maintenance of the hardware, it can catch rust , & then all problems can start. and then the problem starts. For many items, warranty is for 3-4 years. If the problem is solved by alignment then that’s first thing which is done else part is replaced by the company.
Kitchen Trolley do not catch rust as they are made from steel. A good quality soft close hardware has good channels which can last more then 10 years. The hinges & channels which are used in wet area or which come in contact of water have more chances of catching rust.
If the shutters are made from marine ply or commercial ply they will also not face any problem as they are good quality ply.
Be careful of really cheap & low quality kitchen hardware , there is no guarantee with it. It will cost you half the price compared to branded hardware when you buy it but it will not last as long as good ones.
Recently we found a Vendor from Pune, who was selling pretty low quality products for big price. His business model was to sell 2000 rupees item for 10,000 & in next 5 years even if couple of customers returned products , it wont hurt business. Unfortunately, in India, when you dealing with unbranded items make decision with bit wisdom. if something sounds too good to be true it is probably false.