Required fiddle: http://jsfiddle.net/q3yc3gap/ reproduced here for clarity:
/**
init event not being triggered
**/
function algo(message) {alert(message)}
algo('works')
$(".slider").on('init', function(){algo("doesn't")});
$(".slider").slick();
/* Alternative cases */
// $(".slider").slick().on('init', function(){algo("doesn't")});
// slide = $(".slider").slick();
// slide.on('init', function(){algo("doesn't")});*/
The "reInit" event also
The fiddle complains about http over https, and the scripts are blocked:
Blocked loading mixed active content "http://cdn.jsdelivr.net/jquery.slick/latest/slick.min.js"
Also you seem to have wrong syntax in the example.
This should work, without https and proper syntax:
http://jsfiddle.net/1yvr86yp/
@gausarts you are right. Shared the wrong fiddle.
The code pasted in the report is right though.
Your fiddle doesn't work too.
Hmm, perhaps you are seeing it while logged-in?
Try logging out of the fiddle site, or see it in another browser as anonymous.
It is a matter of slick script is being blocked as the above error says, you are using HTTP inside HTTPS.
NOT WORK:
https://jsfiddle.net/1yvr86yp/
WORKS:
http://jsfiddle.net/1yvr86yp/
Or better you change the loaded slick.min.js to use HTTPS, and vice versa.
Maybe I wasn't clear. Slick works, as in: the slide loads correctly. The callback for the init event just isn't triggered.
No caca.
Strange, I see "caca". Perhaps your browser blocks the alert message, then?

Weird then... Nothing blocking the alert since this shows _coca_ http://jsfiddle.net/0dnn51tn/ but not _caca_... weeird.
I see both coca and caca respectively.
Perhaps you'd better use console.log(), or do other useful function?
Well... this is the demo. I have tried actual code on the project I'm using slick in.
I'll try another browser in a moment and see what happens. Thanks for the time anyway.
Hi !
I've the same problem. With jQuery v1.11.1
Can't fire/listen init event.
@tutuca - Your JSFiddle works fine ( see picture below )
@tonioMtl - JSFiddle please?
@gausarts JSFiddle is working fine ( http://jsfiddle.net/1yvr86yp/ )
I'm going to close this unless someone can provide a JSFiddle and clear evidence of the init event not firing... even in one specific browser or scenario... currently I see none :confused:

Please add to the docs that the init listener has to be defined BEFORE the slick object.
Thanks @nikolowry and +1
@nikolowry thanks! this was my issue. Syntax was spot on, but the order of my JS was incorrect.
@simeydotme it would be great to get this added to the documentation to help others.
Thanks @nikolowry and +1
PLEASE put this in the documentation. This caused quite the headache for me, too.
&& massive thanks to @nikolowry. :)
Also giving my +1 to @nikolowry for his heads-up answer.
Perhaps an alternate way to handle lessening the confusion of when this and the 'reInit' handlers need to be defined would be to pass the handler functions into the settings object (maybe in an 'events' container object).
I've found a solution to this problem, just call the on('init') function before the slick function
This got me too. If the docs showed the event listeners in the context of the slick function it would remove a lot of confusion.
Thank you @nikolowry !
I was bumping my head for ages to get something to work on init, never thinking it should be put before the object itself. Thanks again!
3 and a half friggin years, still no mention of proper order of operations in the documentation. Does no one care about clarity and detail anymore? I started on Bootstrap's carousel and that is so full of errors it's not even usable. This one's way better, but how about listening to feedback and making improvements.
It looks like the docs are updated on the repo's README to clarify this issue, but not on http://kenwheeler.github.io/slick/
Most helpful comment
Please add to the docs that the init listener has to be defined BEFORE the slick object.