Inline validation informs users whether what they type is valid as they type. The theory is that it’s easier to fix errors as soon as they occur instead of waiting until submission. The thing is, inline validation causes several problems:
For fields thats require a certain number of characters, the first keystroke will cause an error. Meaning users will be interrupted early and often.
We could wait until the user has entered enough characters but this means the only way a user will get feedback is after completing the field successfully which is pointless.
We could provide feedback when the user leaves the field (
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