Even though the animals have finished building the windmill, why don't they have the promised comfort that electrictiy was supposed to bring them and how does Napolean explain this change of plans in Animal Farm?
The animals never get to see the advantage of the windmill because every time they build it something happens to it. They are always working toward progress, but progress never comes.
Snowball promises the animals that the windmill will make their lives better. The animals have never seen electricity before. Snowball fills their minds with ideas of fanciful machines and easy life.
The animals had never heard of anything of this kind before … and they listened in astonishment while Snowball conjured up pictures of fantastic machines which would do their work for them while they grazed at their ease in the fields or improved their minds with reading and conversation. (ch 5)
Soon the windmill is dividing the farm. Napoleon is against it, mostly because it is Snowball’s idea but also because it stops the animals from producing food he can sell. Snowball suggests that the animals will only have to work 3 days a week. The animals all align with either one, except Benjamin because he says it doesn’t make a difference.
After running Snowball out, Napoleon tells the animals they are going to build the windmill, but it will be a lot of work and he’ll need to cut their rations to do it. The animals are willing to sacrifice in the short term for the promise of long-term gain. The windmill was his idea, he tells them, not Snowball's.
The animals were not badly off throughout that summer, in spite of the hardness of their work. If they had no more food than they had had in Jones's day, at least they did not have less. (Ch 7)
Napoleon tells the other animals that the "needs of the windmill must override everything else," so they need to trade with other farms. Until it is built, they must sacrifice.
Of course, the windmill is nothing more than a scam. It is the promise of progress, and it keeps the animals busy and motivated. In reality, Napoleon will never let them finish it and live the easy life. He needs to control them, and does not want everyone equal. He wants to profit off the other animals, not share the profits with them. The windmill is just a diversion.
The animals do not pick up on this because they assume that unlike Jones, the pigs and Napoleon have their best interests at heart. By the time they find out otherwise, it is too late.