The biggest issue with this is that caffeine has a strong habituation effect.
That means, if you consume the same amount of caffeine each day, it only takes between 1 and 3 weeks to get to a point where the caffeine does nothing for you. And what's even worse is that if you then stop using caffeine, you get basically an opposite caffeine effect, meaning you are more tired than if you had never used caffeine at all.
That's why so many coffee- or energy-drink-drinkers say they can't start the day without caffeine. Because they are habituated to their caffeine intake, and if they don't have their coffee/red bull/black tea/... they literally crash and are much more tired than if they never used caffeine in the firsst place.
So if you want to have any positive effect of caffeine you have to cycle it: use caffeine for a few days, then don't use it for a few days to make sure you don't get habituated to it.