Validation message review about using ! and using short, direct messages

Question

Is is appropriate to put '!' at the end of validation message?

It is good to use short and direct message such as "xxx required" or "Enter xxx" right ?

Answer 1

I think the exclamation marks are a little harsh considering that the messages are red as well. I also am not fond at all of the short messages, some of them are a little confusing too. I'd also get rid of 'Capital Case' too.

I'm a big fan of this writing style, keep it simple and not too formal.

Enter a first name
Enter a last name
Enter a valid email
Enter a password
Must match the password field
Enter a mobile phone number

Answer 2

Having an exclamation mark is unnecessary in the message. The messages themselves are fine - short and to the point and don't need the extra emphasis an exclamation mark brings. If you can outlining the text boxes also helps to draw attention to the ones that have errors. It also provides something for a tooltip to be displayed on.

The only time I'd use an exclamation mark would be if space were tight and I needed to display something to show there was an error. The "!" could then be used as a hover target for a tooltip with the actual error.

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