First the question is, how do people go about designing a responsive website? Well there is a term called Gradeful Degradation. What that is is that designers wanted to take advantage of new technology without excluding users with old setups.
What came up was this –> create and serve the best experience possible, and then design for each possible degradation of technology at the client side, and ensure than no matter how low the client-side technology gets, the site would remain functional.
With mobile web-design, this meant that a full website would scale back and gradually remove features as the screens (and processors) become smaller and simpler (viz. No flash support etc.)
The question is, should websites be designed as a responsive one of should a separate mobile website be designed, which is loaded when the client is a mobile browser?
The good thing about responsive websites is that you don’t have to make different versions of websites for mobile and desktop, hence less work is needed and there isn’t any problem of different information written on mobile and desktop versions.
But the bad thing about responsive sites is that most of them are not being built mobile first. Instead a lot of responsive designs take desktop sites and simply hide things using techniques like display: none. So in this mobile world, they are being built for something else.
Also responsive sites are focussed on display, putting performance on the back burner. A slow loading website miffs1 many mobile viewers.
Having a separate desktop and mobile site means that you can start thinking of different designs from the start. This is something like Indian Express’s site does. It has a different way of showing news on mobile than in desktop, even though the colours are the same. As a result, its performance doesn’t suffer.
The bad thing is of course if you forget to update any one of the versions, then you’d have different information on two versions. To get rid of this problem, you have to use lots of programming (PHP or others) to make the websites so that putting information in just one place is enough, but then that makes the website building complex.
So the answer comes down to, if you have a big website which is a pain to download, then building a mobile only site is good, sans the images and heavy stuff. Prepare lots of code for it to update both versions simultaneously.
But if your website is small or smaller audience, then making just one website is enough. Not because it’s better, but because you don’t have the time and energy to make two versions
1. Miff = Annoy, turn people off.