Having looked at the time-lapse:
I suspect you might get a better answer out of gardening on this one, but I think it is entirely water related and that you are underwatering or watering poorly. It could also be that there is some problem with the pot - it may not be draining properly and the water is pooling in the bottom, which can cause root rotting.
What happens when you let a pot dry out is that when you add water, it takes some time for the soil/potting mix in the pot to hydrate. In fact, the potting mix can even become hydrophobic, so even though you see water flowing through the pot, it isn't actually soaking in.
Water won't be taken up immediately, it takes some time to soak into the potting mix, and then be taken up by the roots and transported to the leaves.
If the pot has holes in the bottom, try soaking the pot in water from the bottom once a week (I suggest about 1h - stand it in a tray), rather than adding water to the top, and/or more regular watering.
The plant you have is a Coleus, which are good pot plants. They do, however need regular watering, about every 2-3 days and good drainage to do their best. There is a good guide to growing them at TheSpruce.com.
I would say, the pale colour of the leaves is an indicator that it is suffering in some manner. There are a few possible causes - it possibly needs a bit more sun, but the few hours in your window should be enough. Having said that, the pale colour could also be from nutrient deficiency, particularly nitrogen, or caused by being too dry. The dry edges/tips on the leaves also indicate that it has been too dry at some point in the past few months.