Job interviews are designed to assess you in three areas: personality, aptitude, and experience. Just because you have the skills and work history to do the job, doesn't mean you'll get it. Hiring managers also needs to feel your communication style and ability to adapt to the corporate culture are in sync with what the company needs. As a result, hiring managers like to ask behavioral questions designed to get you to open up and share more about yourself. These questions can be very tricky to answer. Especially, questions focused on your previous employers and your reasons for leaving.
Resigned or fired? It doesn't matter, something went wrong - and the hiring manager wants to know what it was.
If you are interviewing for a job, then something about your current employer is falling short. And, if you are currently unemployed, then something definitely happened with your last employer that didn't end well. Either way, the answer is difficult to articulate.
You have to be extremely careful not to allow too much emotion to creep into your response.
HR professionals are taught early on there are three sides to every career situation: your's, their's, and the truth. That means you have to try to present the facts as objectively as possible. If your answer is long-winded and shares how you were wronged, or why it wasn't in any way your fault, I guarantee you won't get hired. One of the biggest mistakes job seekers make is blaming former employers. Accountability is key. You need to own the situation. You were the one that took the job. You worked there. As the saying goes, "it takes two to tango."
So, how do you answer without throwing the employer under the bus?
The key is to walk the hiring manager through a set of events leading up to the point where the job no longer met your needs. Talk about what you experienced, what it taught you, and how you have come to realize it's no longer a fit for your needs. It's called the Experience + Learn = Grow model for answering interview questions. And it's the safest way to respond. For example, if your current employer doesn't pay enough and you feel you are worth more, you might say:
"I've learned a lot in my last three years at ABC Corp. I've been able to increase my production level by 30 percent. However, when I sat down to discuss how I might earn more money this year, I was told there wasn't room for a raise. I am passionate about growing my skills and my income. So, I realized it was time to see if there might be a new opportunity where I could leverage my higher skill level to grow, while earning something that seems in alignment with the value I'm providing."
This answer is factual and neutral. It doesn't put down your employer, it simply explains your desire to earn more.
P.S. - Don't forget to end the conversation on a high note.
Once you talk about why your current or past employer is no longer a fit, it's time to pivot the conversation back to why you want the hiring manager's job. Being able to connect yourself to the organization's goals is vital. Hiring managers need to be reassured their job is more than just a way out of a bad situation for you.