Warning, Stop not appearing in Shiny Server

My R code has many validation checks built in using stop(), warning() and such. When I run my Shiny app locally on my own machine (and when these warnings and stops are triggered), they print on screen in the shiny app.

However, I replicate that same issue running my app on shiny server pro, all I see on screen is:
An error has occurred. Check your logs or contact the app author for clarification.

An error has occurred. Check your logs or contact the app author for clarification.

I plan to write validation errors inside my shiny app (using validate(need...))), but curious why the warning and stop errors seem to print on the local version but not when running from shiny server?