Question: In the very first episode of Transformers, you see them on Cybertron, millions of years before they crash land on Earth. Why is it that Optimus already resembles a semi truck? The truck parts are visible, the windows, doors, and tires and such. They don't scan Earth to look like vehicles till millions of years later. I never understood that.
Question: When and how did the Great War end? I know the original Transformers ended its US run after the 3-part Headmasters, but Generation 1 continued on in Japan in Super God Masterforce, Victory, Zone, Return of Convoy, and Operation: Combination. Which cartoon ending is considered "official," the US one which finished its run in the 80's with Headmasters or the Japanese one that ended in 1992 with Operation: Combination?
Answer: It is whichever ending you want. There is no 'real' set or canon ending to the war. The only semi-resolution is Beast Wars occasionally hints at the Autobots winning (before the Maximal upgrade). However, Beast Wars is a combination of the US cartoon and the US comic, and excludes most of the Japanese continuity. So it is really up to you as to what you want to believe. Most people seem to 'accept' the US universe, ending with Beast Machines.
Question: What is the true origin of the Constructicons? "Heavy Metal War" claims they were built on Earth by Megatron, but "The Secret of Omega Supreme" shows them already on Cybertron before the war on Earth began. Is this a legitimate mistake or is there a reason behind it?
Answer: This was actually one of many errors in Transformers, the Constructicons MUST have been built on Cybertron, the only transformers genuinely built on earth were the dinobots, reason being Vector Sigma has to give personalities to each and every robot, else they end up like the dinobots, very simple and dumb. For reference watch the episode "The Key to Vector Sigma" which introduces the Stunticons and Arielbots - both Megatron and Optimus Prime have to go to Vector Sigma to get decent personality traits installed, prior to this the new robots are controlled by remote controllers and have no AI.
Chosen answer: The toys came first, the cartoon and the movies came later, they were hardly going to let a small detail like that get in the way of business. So basically it's a deliberate mistake.