Failure concept and workplace

I would like to further understand the concept of failure at the workplace. While I understand that the only thing that can happen with failure is a feeling, I am not so clear when it comes to failure at the workplace. Indeed, it seems to me that If I do not meet the expectation of my job, I may get fired. I understand that what is being referred as failure is not failure to deliver the expectation in a job but to failure to deliver expectation set by myself.. is that correct? However, not delivering the tasks expected and getting fired is something I would call failure.. I am therefore a bit lost in the way to understand this concept in the workplace. Thanks