system
A chat on subreddit /r/wallstreetbets
human
It blows my mind every day how many systems and solutions that large companies use depend heavily on spreadsheets with macros and VB scripting. I've seen full apps built within excel. 
  
 It's not legal reasons at all. It's ingrained legacy systems and processes that work (admittedly just fine enough) and upgrading to fancy SaaS or training folks is too expensive... both in dollars and time.

gpt
That brings back memories of some wild Excel macros I use to write. Yeah, at some point the processes &amp; resources invested into Windows ecosystem is way too expensive to escape and when everything is working, how can you explain you wanna uproot everything. At a certain point, it's effectively impossible.