You're probably getting down-voted because (aside from the off-topic comment) that isn't how copyright works. In most cases copyright starts from the time the work is created, and lasts for a specific period of time (Disney-style exceptions notwithstanding), whether copyright is explicitly declared or not.
The copyright notice only serves (informally) to indicate the start-point for this time.
I think the idea is addressing these people (like me) that were used to seeing those "Last edited on XX-XX-XXXX" notices at the footer of HTML pages and worry that the project may be dead/outdated if the date is old.
Now that I think about it, is this why people puts "Copyright $initial_year - $current_year"? Because as you rightly say, only $initial_year is legally relevant.
> Now that I think about it, is this why people puts "Copyright $initial_year - $current_year"? Because as you rightly say, only $initial_year is legally relevant.
Both are, actually, and $current_year may be the most relevant. That formulation generally indicates that the current work was created in $current_year, but is a derivative (possibly through a chain of intermediaries) of a work created in $initial_year.
Derivatives are independent works with their own copyrights, and copyrights of works where the author for copyright purposes is a corporation rather than a natural purpose last a fixed time from the creation of the work in the US, currently, IIRC, 95 years.
So something that says (assuming accuracy of the notice) Copyright 2001-2017, with a corporate author, will be out of copyright (barring further extensions) in 2102, but is ultimately based on an earlier version that will be out of copyright in 2096.
Of course, a lot of websites use automatically updating and false dates for copyright notices, and anyhow the usual current advice is not to include a date at all.
Hmmm I see, I didn't assume people meant that the subsequent updates of the website are intended o be considered derivative works, but for instance by similarity to different editions of a book, I guess this is actually the case?
The copyright notice only serves (informally) to indicate the start-point for this time.