Leftpad doesn't work when concatenating with "+" (and number-like strings are converted to numbers)

[Pch]

You’re not the first one mentioning this (or alike) in those past few days

String concatenation failure

The following formula: ":"+"004" returns the string ":4" All zeros are gone. What happened? Meanwhile, I use the workaround: Format(":{1}","004")

I have no idea if it’s intended or not though …

But I like this point of view concerning this trouble :

String concatenation failure

The + is like concatenate() but not exactly because it can also do maths (addition). Because of this, it tries to do math on things and appears to be treating your “004” as an integer; since 004 = 4 as an integer, it drops the preceding zeroes. concat(), concatenate() and format() are great ways to get around this nuance.