Why open source matter - SensorsUnleashed/Contiki-Device-Link GitHub Wiki

A closed source company that shuts down, could in worst case break your equipment; its not even safe to buy from the big vendors, see this example. In an open source project, anyone can continue the development.

Privacy. If the source is closed, how do you know what data is flowing in and out your local network. Information can worst case be used to determine if your at home or not. The wrong people might find this information useful. Some companies any personal information to generate a profile about who you are, where you are and why.

Security. Closed source projects, often ship their products, and forget about them afterwards. The risk is, that someone can take control of your devices, but the company refuses to patch the vulnerability. Just take a look at most mobile manufactures.