Why does the Laser exist?

The Laser was lighter, simpler, cheaper and available off the shelf through a network of dealers.  It was (and probably thill is) great fun to sail, if not wetter.

There was also a ready market in the UK of 1000’s of sailors looking to progress from Mirrors.

Because many of us love it, and because we don't get broken up sailing on in F6.

Other interesting questions are why does anyone buy a new design like the H2, which weighs as much as a 1960s design?

As its creators told me, partly it was smart marketing and the right boat with the right production; partly the right time; and partly something no one can work out.

On the physical side, it arguably had a newer style of hull than any of the listed designs bar the Contender, and it had an advantage over the Contender because it was much lighter as well as being more of a mass-market boat. The use of foam sandwich in the deck was also pretty novel at the time. It was also a boat created by an industrial designer as a bit of an exercise in minimalism, and Kirby understood that aim right from the first doodle over the phone.

One thing that interests me is that the boat is a long one for its sail area, freeboard, weight and length. Adding length is one of the best ways to make a boat perform well.  Long, light boats with comparatively rigs tend to be good allrounders, and IMHO one of the Laser's strengths is that it performs well across a wide range of conditions.  

It was at the right time, because it was around when dinghy sailing was still huge and around the start of the big swing to singlehanded sailing. And while it had a small marketing budget, it was very well directed. The boat also got very positive independent reviews for its simplicity, modern appearance and speed even from its first showing at the America's Tea Cup Regatta, when it was still a speculative project known as TGIF.

The other thing, of course, was that it kicked off in North America where it had less competition in terms of good rival designs, and (as Ian Bruce told me) it wasn't in competition with the Finn etc because it was initially seen as a top sailors like Peter Barrett as their "other" boat; their strict OD fun boat for when they were not sailing their Finn etc. 

What may be a significant factor is that around that time, the Moth had recently changed from the wingless scow/Europe style of boat into a more fragile and exotic racing machine. That seems to have been particularly critical in the USA (where the old wingless and short-winged Europe-style Moths had been enormously popular on the east coast) and Australia (where the wingless scow had been the #1 singlehanded class).  The newer Moths were less friendly to the typical club racer and that left a gap for the Laser.

I still remember the first time I saw a Laser. I was about 10 and a former sailing journo had the Australian rights. He brought about half a dozen of them to my club and lent them out for racing on a course about 30 metres long, inside the marina, on a sailing day.  A bunch of top sailors went out on these super simple boats, which were faster than a Moth because of their length and design and as fast as a Contender in light airs, and bashed them around and had a great time. As I recall, one of them - a Moth national champ who had developed the hard chine scow - came straight ashore and bought one. It was great marketing that emphasised simple fun on a tough, one design boat that performed well.

Yes, but if people want to be negative about someone else's class then one can point out that the H2 is heavy and dog slow for a 201X boat.

Personally I don't like being negative about other classes, but I don't see any reason to sit back when the sniping starts.  Obviously no boat is perfect, but implying that a class should not exist at all is being rather extreme.