These days companies / manufacturers of all kinds of products seem to have this tendency to ruin their perfectly good, established brands or products by introducing some sort of change to them. Not all change is bad, of course, but often the driving force behind these changes is pure capitalist greed, the bottom line, aka money. Changing something to make the production costs lower can be one of the reasons for these things, but there can also be perceived "fashion" trends that can lead to missteps.
Whatever the reasons, this silly little web-page lists few consumer products that I have been previously happy with, but have gotten dissatisfied with after some kind of newly introduced change in design, formula, or such. The views presented here are, of course, personal and largely subjective .. someone else might see things very differently.
It should also be noted, that I am using the word "ruined" to make a point, things are not in all cases as clear-cut or bad, of course.
As I stated above, not all change is inherently bad. Change can be, and often is, for the better. However, as also stated, there are varying reasons for change and not all of them can be considered "good". But even the motivations may or may not matter for subjects that are, well, subjective - or perhaps even objective in some aspects, at least on an individual level.
Take the "Fairy Ultra Original" case below as an example: the change of fragrance has both subjective and personal-level-objective issues for me: I do not like the new smell, but it also truly gives me an headache, for whatever reason. Whether it is psychosomatic or not, I cannot tell. Thus I like to at least think that the change has been "objectively" bad for me, but also on subjective level. Someone else might very well enjoy and prefer the new version - but then again, if the change in formula was only due to the scent, why not create a new product line? As an eternal pessimist, I tend to lean to suspecting financial reasons as the driving factor.
Sidenote: I am aware that many companies have "regionalized" versions of their products, usually with different scents or so. It is possible that in my encounters a shop/importer has bought a batch of such product meant for some other country's or region's market .. so .. shrug.
But from a customer's perspective it is neverthless annoying to buy something that you expect to be (and stay) like something, especially if it is branded and marketed as the same old thing .. only to find out that this is something else.
Electronic device manufacturers tend to do this all the time, and while I have encountered this many times, I'm not currently going to list specific examples here. Usually how it works is that they change some component(s), without making any changes to model IDs .. or if they do, it is done very subtly, basically to fool people.
Of course this may not matter for all instances, and sometimes the changes are not made for "nefarious" purposes. They may be revisions fixing issues, for example. However, sometimes these are cost-cutting measures that may even break compatibility.
Some of the examples I have personally encountered are few WiFi dongles and USB flash/thumb drives, which are purported to be the very same model of the device, but in fact contain very different chips. In case of those WiFi dongles, this resulted in the "new" devices not actually working with Linux because it was not actually the same device.
And the USB drives had worse performance. They were purchased from same reputable source, and while counterfeiting is always theoretically possible, I have no real reason to suspect it .. other people have reported on these things occuring for many (supposedly reputable) manufacturers devices.