Sometimes conspiracy theories turn out not to be theories at all.
In this fascinating video, we are shown the common practice of intentionally baking a self-destruction date (known in the business as planned obsolescence) into the things we buy.
The conspiracy is to make inferior products and then ensure that it is difficult or impossible or super expensive for the consumer to easily fix them (known as the right of repair). The only option is to buy another one.
The second part of the conspiracy is to regularly manufacture a new style. That is, to manipulate the psychology of the consumer (via advertising and other methods) so that we become discontent with the model we have and want the latest new thing (which oftentimes have little (besides aesthetic) significant improvements.
I am totally guilty of this. All the time.
Manufacturers increase profits at the cost of increased waste, depletion of natural resources and plain old frustration when the thing you purchased not that long ago breaks down.