Because it is a timed messagebox. That's what the last parameter does.
>How will the user dismiss the message without a button?
>
>>I thought this would not display the Ok button, but it does. Is there as way to have the messagebox with no icon or button?
>>
>>=MESSAGEBOX(ALLTRIM(oValidateResponse.SubLast) + ', ' + ALLTRIM(oValidateResponse.SubFirst),4096,'Eligibility Validated',1)
>>