It can be, that your webspace provider has an older PHP version installed or your webspace is so cheap, that PHP is simply not available at all. Or maybe there are considerations about security. Or your webserver is short on CPU power, like it may be the case for smaller systems, like Raspberry Pi or such. Or you would like to take your whole article base with you on an USB-stick. Or you'd like to deploy articles on a regular base to a distributed file sharing system, where a running PHP installation is not possible, just sending files.
Because Blogless beeing very minimalistic, it is possible to drive your website completely without having PHP installed on your webserver. What's the trick? Well, for shure since Blogless is written in PHP, you can't use it without PHP. But you can split the generation of articles from the hosting of articles.
Installation of a local PHP setup
Just install a pure PHP installation, for Microsoft Windows for example you would get it here. Install it on your notebook or desktop, download the latest version of Blogless from Github and make use of PHP's internal webserver to run Blogless on you computer. This is the batch file blogless.cmd I use to start the webserver locally, you need to adapt the pathes:
rem adapt the PATH fitting your local PHP installation
E:\php5.6\php -S localhost:8080 -t "E:\htdocs\blogless\"
Blogless is now generating webpages, which you can afterwards upload to your remote webspace. Beware to first correctly set the base url according to the target, your webspace at your provider. Also take care to leave out the admin directory - this is blogless itself and it will be of no use on a webspace without PHP.