Well at least it is not "life threatening", unless it happened to be a computer controlling some kind of "life support system" in the critical care section at the hospital.
Yes, but it doesn't do any favors to newbies to tell them that.
The first thing a "newbie" needs to understand, is what the consequences of mixing repos may be, and also some things that just plain don't work, this is especially important when perhaps a student, and all his/her school work is on the one system, on the only laptop they have, or also a small business, or "production server". Until the "newbie" or less experienced person, regardless if it is a student, or professional, business, until or unless the individual expresses the desire to experiment and try some modification, etc. then it is fine, to encourage them, it is a great learning experience to try new things, but they need to understand that should also be done on a seperate machine, (ideally) or at least partition, or a VM, and not the OS they depend on.
For example, also, telling people they should not mention which distro they are using because this is a Debian forum, and they might not get a response, or might get told to ask some where else, that kind of advice could lead to creating a "mixed" system, in reverse, getting stuff from the Debian repository, when they should have been using the
repository for that particular distro. Like wise , downloading what often is just "linux" software, from unknown sources, there is a lot of "linux" software out there, and it is obvious the developer does not really know enough about "linux" and all of the distros to take that into consideration, maybe they just test it on "ubuntu" , and then say, ok , This works on linux, but they have no clue if it really works , on Debian, or any of the other distros.
I am sure most people here have noticed, but if not, take a look at the install manuals , on some of the better "open source" software, and they will see that the install manual includes different instructions, specific for Debian, or Arch, Ubuntu, and some of the other most popular distros, and the instructions are different,..very important to read the "read me first", etc.
Some times, I have found in the "read me" file, it says, "If you are using Debian you need to, bla, bla,(usually a url and reference that you need to be sure to get the libraries needed from the Debian repository).Or in some case I have seen where they admit,and make it clear, that that particular package, has had problem working on Debian.
I know, because I learned the "hard way", installing a "control panel" ,or trying too, for a server. I thought I followed the instructions carefully, well I did follow them carefully, but after the install, it (the program) would not run, it was late and I was tired,..my second "fatal error", I shut the server and computer down, went to bed.
The next day when I started the computer,.. could not boot, to the partition that had the server. So I booted with a different partition, and went to the site where the manual, and install instructions were, to see if I could figure out what had gone wrong. When I started reading, carefully again,.. I noticed it said " for archlinux", and further down,"for Debian "squeeze", for "Lenny" see this: (a url link for debian "lenny"), and further down,
"For Ubuntu", etc,various distros.
Well, the night before I had not payed attention, and had started following the instructions on the first part I saw, so I guess that was "Archlinux",..this was so long ago, don't remember exact details, ..but any way, I compared some parts of the instructions, with the instructions for Debian, and they were different, ... especially different on the sources that I was supposed to use, to install certain libraries, (dependencies), that did not come in the software package and needed to be installed first. I was lucky, and was able uninstall, purge, etc,..and got back to where the "Squeeze", partition would boot , and was able to successfully install the software.
Kind of a Too Long of A Post, maybe not very many will read it, my feelings though, ok, if that is what one enjoys, experimenting and crashing a system just to see if they can fix it, go for Have Fun !, But well, maybe it is cause I am older and wiser now, Life is to short to waste parts of it trying to do something that is impossible, or extra hours, re-installing and starting over, I would rather be doing other things, then running in circles, waste valuable time.