XCode: The file “[APP NAME].app” couldn’t be opened because there is no such file - objective-c

Question

For context, I am encountering this immediately after resolving this issue:
Xcode error: unable to create directory '/[PATH_TO_APP]/[APP_NAME].app' (in target '[TARGET]' from project '[PROJECT]')
Here is the full error details text (with redactions in [] for privacy):
Details
The file “[APP NAME].app” couldn’t be opened because there is no such file.
Domain: NSCocoaErrorDomain
Code: 260
Failure Reason: The file doesn’t exist.
User Info: {
NSFilePath = "/[APP NAME].app";
}
--
The operation couldn’t be completed. No such file or directory
Domain: NSPOSIXErrorDomain
Code: 2
Failure Reason: No such file or directory
--
System Information
macOS Version 10.15.5 (Build 19F101)
Xcode 11.5 (16139)
Running ls -l in the project folder shows the [APP NAME].app now present, but navigating to the same location and selecting the file in Finder shows a "crossed out circle" over the app's icon. Removing the file and building again results in the same thing. I've also tried renaming the project and restarting, etc, to no avail.

Answer 1

NSFilePath = "/[APP NAME].app" feels like a missing or misspelled environment variable.
If the build expects custom environment variable like $(MyBuildDir) to be defined, when it's not, then running a command with $(MyBuildDir)/[APP NAME].app would result in "/[APP NAME].app"
The same is true for if the environment variable misspelled. For example, using $(UBILD_DIR)/[APP NAME].app instead of BUILD_DIR would result in "/[APP NAME].app"