Since the regulations relating to nicotine containing liquids came into play, the old hands who have made quality liquids for many years have stepped back a little.
Not through choice, the issue is that while most end consumers are seeing - as
@MrTeaTime says 'relentless' releasing of new juice lines - we are seeing the impact it is having on the businesses trying to put out 'proper' premium quality stuff and it's an uphill struggle.
It's partly because there's just so much of the new stuff coming through, allowed due to the really impressively poorly implemented regulations and the MHRA changing their minds on what is OK and not more times than they breathe air and the non-existent enforcement at an early stage by Trading Standards. What happened is just that the old Facebook homebrewers got wind that it was not only business as usual but pretty much given the all clear by MHRA to continue as planned.
The other reason, and this will be contentious with those of you who already have the opinion that good quality eliquid is 'overpriced' is that the current market price these shortfills are coming out at is designed to undercut each other on every new release in order to get into as many shops and homes as they can before the others beat them to it. The trouble is that it's not a sustainable price point if you meet the criteria of putting good quality ingredients, research and development, genuine business overheads, quality control and customer service/support.
The knock on effect is that consumers start to see juice prices collapse - great for the buyer, not so great for the long term plan of staying in the vaping business as the good old dirty 'profit' is what keeps businesses afloat. If the margins on juice become too small then you will see the types of quality manufacturers you want to see stick around will just wind up and give it up as a bad job.
Another issue that many of us have is that the costs of going through TPD compliance as has been stated elsewhere quite succinctly - ruinous... Most of us that paid what some may spend on owning a house to go through the right side of the TPD had an expectation that while some may exploit loopholes they would not be left so wide open as to literally create their own grey market and as a result things would eventually stabilise enough for us to then invest further in new flavours that have since fallen by the wayside as we release shortfill versions instead.
None of us (I mean this in all honestly not a single eliquid producer I have ever spoken to) like the 10ml bottle size rule and it's pretty much the one rule that is crippling the industry. Vapers like big bottles, they don't mind adding their own nicotine in order to get around this loophole and as such shortfill became a huge open workaround. If the lawmakers had understood this then TPD compliant manufacturers would never have been put at an actual disadvantage to non compliant shortfill but this is the reality of what the business has become.
Shortfill is the most appealing option for many people because they find 10ml bottles a pain in the arse, wasteful and having a 60ml+ bottle is a far better option than many little bastards.
With the amount of research time, testing and refining, getting things perfect and then paying for testing and registration, it is understandable that their output has gone down. Where these guys offer shortfill options they are generally nic free versions of their tested recipes and as such are still good.
Some of the established makers have obviously seen their business drop and as such have jumped into the nic shot market with both feet, making a flavour that seems ok to them and matches the current trends (more on this later), then onto the market it goes.
Absolutely, in order for this development process to continue there has to be the business coming in to not only make back the costs but a little on top, it's all about that dirty profit again. Instead as we probably have the most to lose, having put tens of hundreds of thousands on the line previously for testing - we just release them as shortfill. In our case we have shortfill big bottle options of our best selling ranges to try and give high volume users a fighting chance of having their ADV juices in decent, useful sized bottles. For the rest, they are made exactly the same way, with the same ingredients, QC, and after care as every other one of our products. We still thoroughly test shortfill recipes over long terms before they are released so no loss in research and development either.
There is a growing trend at the minute that the current price of everything is considered too expensive, people naturally seek out bargains and I think that in terms of the cost of vaping vs smoking the price comparison may have been somewhat lost too. Yes there were people buying baccy or duty free cigs that were vastly cheaper than over the counter but that's an invalid comparison as eliquid isn't made duty free or on the snide (in the case of decent manufacturers)
At nearly £10 per day for a pack of 20 I would have been spending £40 a week on my smokes, I have a tank that with one coil type I can go through 8ml a day so that's around the same cost as smoking for me (not including the health and lifestyle benefits).
However...
The very same tank with a different coil means that I not only half the power needed to drive the coil but use 3ml of juice per day - half the cost of smoking and other than going from obnoxious clouds to most I get semi obnoxious clouds - ideal for me as I vape to not smoke and therefore my Procore SE with a 0.25ohm coil at 35w delivers tons of flavour, enough vapour without wasting juice just for show and I take exactly the same amount of nicotine per day. As a comparison the same fitting baby beast or vaporesso quad coils will go through 8ml a day and need at least twice the power to deliver the same hit.
The human body regulates what it needs automatically, using more juice won't mean you are getting more nicotine as your body would tell you to stop before it got too much.
My point is that there is always a more affordable way to vape, if you are in the group of people that used to smoke 10-20 a day but were sold a 150w+ mod and 3mg of juice to switch with then you were mis-sold a product that quite honestly has set you up to consume more for the benefit of the shop and not to work for you. I use 6mg all day every day, dropping to 3mg for me more than doubled my juice consumption and as I am not a big fan of throat hit I instead make all my juice lines as easy on the throat as they can be so my 6mg is not much more of a hit than 3mg in other ranges.