help me to understand how the market works

When I first play the league, I saw that in the market, one divine is worth several hundred exalts. Later on, it rises up to one thousand. Today I check the market and it is around 1750.

To me, it looks like a divine orb doesn't seem to be of much use because when I read the description, it says that it will merely just randomises the numerical values of the modifers on the item. I look at it and it doesn't seem to be of much use to me.

I am just curious and I would like to check with the experienced players on this.

What's the reason why divine orb is so popular and why so many people want it and why there seems to be such a big demand for it such that the price keeps on increasing?

Divine orbs are the $100 bills of PoE. They act as a clean way to store a lot of Exalted orbs by exchanging for a condensed form.

At the start of a league, all currency is worth more despite everyone having less of it. Which is why finding a Divine early means selling it for like 100 exalts, because at that point in time in the league, the buying power of 100 exalts is much much higher than they will be later.

As the league progresses, more players reach endgame and start farming or buying things and trading currency. The result is more and more exalts and divines enter the market, which means the value of exalts goes down since they're quite a bit more common, while divines are still pretty rare.

It's common for players who make a lot of currency early, or find raw divines to just hold onto them longterm like investments and wait for the value to go up before cashing them in.

As far as crafting goes, divine orb's effects are still very valuable, since with enough of them you can guarantee perfect rolls on the range of stats on an item, like say you were rolling a %Physical, %Phys and Accuracy, and Flat Physical damage modifier on a weapon, and wanted all of them as high as possible before moving on to the final steps of crafting like sanctifying or corrupting.