The original batch of Transformers were Japanese toys re-branded for selling to audiences in the United States and beyond. The US company Hasbro formed an historic partnership with Takara to co-own and produce the Transformers brand worldwide. Both have taken over smaller toy-makers but have never turned such acquisitive attentions on one another. They have worked together for decades to produce the most iconic and many of the best (but also some of the worst) converting robot toys for both children and adult collectors.
The concept behind many of those original Takara toys was that they were mecha operated by drivers. Design focused on depicting vehicles and other machines (alt-modes) accurately. The robot modes in contrast were more abstract - after all a robot can look like anything. As The Transformers however they were re-cast by Hasbro as sentient robotic aliens. They contracted Marvel Comics to develop storyline and characters. Animation models (templates providing guidance to animators) simplified and humanized the robot modes. The cartoon robots and the toy robots looked different from each other but kids were okay with that and the cartoon made the toys into a craze.
There were only so many original Japanese designs and by the third annual catalogue they needed more to maintain sales. With new designs came a new methodology. Now animation models from the cartoon movie (1986) preceded toy design and the focus was for the toys to more accurately match those robot modes. In compensation for this the alt-modes were now more abstract and took the form of 'futuristic' vehicles. As a youth I accepted that only one mode or the other in a toy would be realistic. I had a preference for the robot mode to be more abstract and even valued 'kibbling' (blatant machine-parts hanging off the robot body) as a key part of the distinctive Transformers look. I suspect a lot of kids felt similarly. But some children of the 80s have grown into the adult collectors of today and they are a lot more fussy.
One of the most interesting developments of recent times has been the Generations line of Transformers toys intended to emulate older toys and be consumed by both older children and adult collectors. They have more expectations put on them than the original toys and have to be both 'toy accurate' and 'show accurate'. They cannot just depict a vehicle and a robot. They also have to depict what is now an iconic character in the minds of fans. The designers do pretty well with these expectations but there are some problems that arise from this and one that particularly annoys me is what is known as 'faux-parts'. Imagine a well-known character has windows on its chest in robot mode. In the original toy they were the windows of its truck alt-mode. But for the new version to have both toy and cartoon accurate windows it will be given two sets of windows (each exposed in one mode or the other). This bothers me to the extent that anything so trivial can bother a person. Make the windows turn into the windows dammit! Even if some supposed accuracy is lost who cares? A vital aspect of Transformers is the transformation process and faux-parts detract from that.
My favourite kind of transformation is one that is elegant rather than complicated. It needs a few inventive and non-intuitive twists (like the hip swivel or the head-chest switch) within an otherwise simpler sequence of moves. An extra set of windows is a nasty bit of misdirection for those who regard Transformers as puzzles for them to solve. Another development that I feel complicates transformation is the expectation of articulation. Robots that can assume a range of poses because of more joints can become more difficult to transform because of all that extra movement. A specific set of steps now have a significantly larger number of incremental movements between them.
I must admit that ball-and-socket joints are cool and allow for greater durability as well as posing. Limbs that come off can now be snapped back in. In the older toys if a limb came off then your Transformer was broken. On the other hand it took a bit of force to do that and even as a kid I was careful. And while I love a lot of the original toys I also admit that the capacity to develop finer models has improved. They can now pack more precise designs into toys of a given size. However these finer designs demand more precision manufacturing and I feel the execution often falls short of intentions. Tabs that are supposed to fit securely here-and-there only sometimes work as well as they should.
The original toys had a mix of plastic and metal and rubber and that was cool. As soon as new designs were added they started reducing this variety of materials to only using plastic. The only metal in a toy now is the tiny screws holding it together. The only rubberized parts are sharp bits that would otherwise be a hazard for children. This is all done in the name of profits. Still there have been some improvements - apparently plastics are better made-for-purpose now. Tampographs are way better than stickers. Weapons can be stored on most models now. And 'piping' can give a toy optics that seem to glow.
I'm focusing on toys rather than cartoons but even a toy standing in isolation can tell a story. Look at these toys in robot mode and one often gets a sense of a fictional character with some kind of personality. Transformers were granted personality and alongside that came gender. Our culture so entrenches gender into identity. To start with they were all masculine (except possibly some of the animalistic robots) but eventually feminine characters were introduced too. The moment that happened debate ensued.
How can non-biological constructs have sex characteristics? It was always a difficult question to answer in-story. Now however we are becoming accustomed to distinguishing sex from gender. This concept allows me to say that Transformers can have gender identity even if they are sexless. And this kind of thinking is nothing new. Theology has ventured this for gods and goddesses since ancient times.
Once more the issue of form preceding or following characterization is relevant. Most 'mechs' (masculine characters) start with a neuter toy design. However it is a look that can readily be aligned with the caricatured proportions of masculine cartoon characters. Nobody balks at some boxy lumpy construct referred to as 'he'. However for 'fembots' (feminine characters of whichever faction) in past decades there was an expectation that they must have an exaggerated doll-like form so cartoon models defined a look that was difficult to render as transforming toys. This limited alt-modes of the few fembots that did get toys to more organic and 'shapely' things like spiders (yuck) and motorcycles.
More recently however there have been two interesting developments. One is that designers have managed to make fembots turn into reasonably convincing sportscars or jetplanes. The other is that feminine characters have been allocated to existing and more neuter designs (in a process known as re-tooling and re-decorating) and they turn into things like vans or fire engines. The former development conforms to notions of sexual dimorphism. The latter however recognizes that gender cuts across all sorts of forms. These fictional characters can be 'she' simply because we decide to call them that. The end result is that Transformers are bit-by-bit becoming toys for everyone.
There is so much more I could discuss but I will finish for now by saying that Transformers are intended to be collected. So many of them are made (as a toy or in storytelling) to go with others. Many are designated as having relations like 'twins' or 'master-and-pet' or 'rider-and-steed'. Others belong to groups that form gestalts. Others belong to toy selections who can use the same arms and armour interchangeably. And for me simply the variety of forms promotes the desire to collect. Turning into vehicles is cool but then there are others that turn into monsters or into everyday household appliances. Somehow all these disparate toys can look awesome on the same shelf together in whatever modes. And then they transform!