Why does SM have so many album stock issues?

If I say something will it be controversial I wonder

Imo others sales inflated rather than saying EXO sales are lower. I don’t believe their sales are real. Kek.

idk about new ones but I can answer about the older albums

They constantly changed their publishers and distributors over the years. Some of the companies they worked with in the past are no longer in business. It takes too much effort to make new contracts for publishing and distributing older albums with new companies and it might not be even profitable if it's not guaranteed to sell some minimum amount.

You can guarantee that there are fans that claim their bias would sell more albums if a Company would restock, while that could be true, Kpop Companies can't restock Albums that Retailers have not ordered.

As Album Sales have risen dramatically over the past few years, Online Retailers don't have the luxury of stocking Albums above the pre-orders as Warehouse space is limit. The same is true for Kpop Companies that won't do Production over runs and be left with Albums that Retailers won't order.

Having said all that, SM Entertainment does seem to limit Album Reprints more so than JYPE, both Companies' Idols are distributed by DreamUs, although I'm wondering if it's just EXO

I just ordered 3 exist albums from ktwon4u, and it says there it's still under pre-order, was wondering the same thing!