SQL Server Failed to Alert Operator

I just deployed a new SQL Server Server and set up some jobs. Couple of days later wanted to check the server and see how jobs were executing. I was surprised to find out one job has been failing and I remember not seeing any alert. I did remember that I set up database mail and operators. Job history tells me that sql server failed to notify the operator. I started to look around and finally thought of checking the sql server agent properties. To my surprise I found out that I forgot to set up the properties under alert and putting check for enable email profile, selecting the profile and another check for enabling fail safe operator did all the trick. After changing the setting started to work and sql server agent started to notify me with emails.

HTH