The security initiative known as Secure Boot basically works to prevent third parties from physically hijacking your system by running an alternative operating system. When I first heard about it in 2012, I thought it was a great idea and was all for it. The reality of it since has greatly lessened my enthusiasm.
When Secure Boot is set a certain way, it can present barriers to using an alternative operating system. In many professional environments, Microsoft Windows is a highly productive option. At home, or in other situations, something besides Microsoft Windows may be desired and the ability to recommission a computer with Linux, BSD and a dozen other choices is very useful.
An industry level specification for Secure Boot may be a good thing. It could mean that all operating system implementation could apply the solution in a straightforward way. User menus in UEFI screens and boot device startup directives could be more commonly engaged. Otherwise, arcane methods for adapting Secure Boot to an operating system other than Microsoft Windows could diminish the appeal of setting up such alternatives.
In the worst case, for some, it will mean avoiding computers that are known to be problematic in terms of alternative operating system setup. Companies such as System76 or the Linux division of Dell as well as current and past models of Lenovo Thinkpad could become more attractive. It may also give greater deference to boutique computer makers such as Falcon Northwest, Origin PC, Penguin PC and others.
See the article, Windows 10 to make the Secure Boot alt-OS lock out a reality on Ars Technica.com.