End-of-Life (EOL)/End-of-Support(EOS) describe the final stage of a product’s lifecycle. Once a product reaches EOL/EOS, developers stop updating and patching the product and it is no longer maintained. Software development companies do this often as they release newer versions of their products.
For example, Microsoft suspended support of Windows 7 on Jan 14th 2020 to shift their focus to their operating system – Windows 10 (and future versions). All software development companies do this.
Source: Techopedia
Additional Reading: Get Ready for the Microsoft Windows 7 EOL on January 14th
Related Terms: Agile Development, Waterfall Development, Software Development Life Cycle (SDLC)