It took the Empire 20 years to build the original Death Star in Star Wars, but the second, which was much larger than the first, was operational in just 4 years. Somehow, the Empire was able to whip up the second Death Star almost four times faster than the first. Initially, this may sound like a glaring plot hole in Return of the Jedi, but there is a multitude of reasons why the Empire was able to construct the second Death Star in such a short period of time.
Essentially, the Empire was able to build the second Death Star so quickly because they’d already built one before. Furthermore, Darth Sidious expedited the construction of the second Death Star so that it was functional far sooner than the first. Both Star Wars' original and second Death Star had similar weaknesses, but for very different reasons. Star Wars: Rogue One revealed that the exhaust port weakness in the original Death Star was deliberately placed there by Galen Erso. But the second Death Star’s weakness was that it was incomplete and not properly sealed up.
The Empire Had Paved The Way To Making More Death Stars
One of the main reasons the second Death Star popped up so quickly in Star Wars was because the Empire had already built one before. The original Death Star began construction during the Republic era and had to be kept extremely secret. Even after the Empire took over, they had to keep up the facade that the Senate’s democracy still had weight in deciding the laws of the galaxy. Slowly but surely, the Empire began exploiting innocent citizens like Cassian Andor to build superweapon parts in prison. The final stages of construction on the original Death Star sped up considerably as the Empire tightened its grip on the galaxy.
Another big difference between the constructions of both Death Stars was the order in which they were constructed. The final piece of the original Death Star that signified its completion was the planet-destroying laser, which was the logical order to build it because of security reasons. Had they started with the laser and its construction been discovered, then every planet in the galaxy would have revolted before it was completed. On the other hand, Sidious' main goal with the construction of the second Death Star was to get the laser constructed as quickly as possible.
Palpatine Rushed The Second Death Star, Which Was The Reason It Got Blown Up
The second Death Star’s plans weren’t necessarily stolen by the Rebellion. Instead, Palpatine always intended to leak the information about the second in order to lure the Rebellion into attacking it during Return of the Jedi. Because he expedited the construction and completion of the laser, he hoped to obliterate the Rebellion once and for all with its power. Yet the second Death Star hadn’t been properly plated and most of its innards were still exposed to space. If Palpatine had waited until the second Death Star was fully complete, he would have easily defeated the Rebellion in Star Wars.