I rolled out a feature to my team, and in two days I had two reports of users being blocked by the validation of numeric input fields. The first one figured out that somehow a space got attached to the end, possibly via cut-and-paste. The second one, we worked on it, and there was no sign of a non-digit in the field, but we highlighted the whole field and re-typed the number, and all was well.
You may be thinking "stupid users" but these are not stupid users, these are technology folks. Imagine users who really are "stupid." I think, for usability purposes, the validation of numeric data entry fields should be a tad more tolerant. At the very least, ignore or strip out whitespace characters before attempting a conversion.
John (at) Irie (dash) Inc (dot) com
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