If you didn’t get hired for a job for which you thought you were a perfect fit, it might not be your fault. Sometimes other factors come into play that have little or nothing to do with you.

Here are a few factors that could easily have prevented you from being hired and that were out of your hands.

They hired someone internally. Companies often open jobs up to external applicants because of some HR policy that requires them to do so, even though they already have someone internal in mind for the role. You were never really being considered for the role, but they have to pretend you are.

There never really was a job. Sometimes companies think they’re going to hire someone, so they put out a job ad – and maybe even take applications and meet with some candidates – but the parameters never really get defined, or the project the new hire was supposed to work on gets shelved, and the filling of the half-baked role falls by the wayside.

Another possibility is that a third-party recruiter posted a job description for which there was no actual current position in order to build a pipeline of candidates for roles they are hoping to source for clients.

Budget cuts/restructuring/layoffs. The person who posted the job may have had their budget cut, or may no longer even be there. Maybe the whole department is gone. These things can happen in the blink of an eye and, often, nobody sees them coming. One minute they’re expanding their department and interviewing candidates, and the next everyone is packing up their desks.

You’re overqualified. Being overqualified can be a pain because even though you need a job, people don’t want to hire you because they’re afraid you’ll get bored, leave for something better, or start gunning for their job. Admit it, they not wrong. You would leave for something better as soon as it came along, right?

You’re unemployed. Research shows that employers have a bias against the unemployed because they don’t want to hire someone nobody else wants to hire. It’s ridiculous, yes, because you might be unemployed for any number of reasons that have nothing to do with your actual employability. Avoid this issue as best you can by filling the gaps in your resume with something. Anything.

You’re too old. Studies also show that as we age, our chances of getting hired drops significantly compared with younger applicants. Unfortunately, age bias is hard to combat because it’s hard to prove.

You weren’t a cultural fit. Employers are have been big on cultural fit over the last few years. A 2014 survey found that 43% of employers said that “cultural fit” was the single most important determining factor when making a new hire. This means whether you will fit in with the others in the workplace. Some companies even ask about your favourite music or TV shows. So, wearing a suit to an interview at an office where everyone is in jeans and sneakers might be a red flag.

This doesn’t mean you don’t have to research the company culture and do your best to highlight how you do fit. But you can’t necessarily force it.

The employer has no idea what they’re doing. Just because you didn’t get the job doesn’t mean you weren’t the person who would have done the best job. Sometimes employers make the wrong decisions and hire the wrong people. Cultural fit, for example, has its critics (myself among them) who believe strongly that diversity – not homogeny – helps companies thrive.

At the end of the day, all you can do is your best.

If you write an amazing cover letter and resume, prep for the interview, research the company and role and put your best foot forward, you’ve done all you can do.

There’s no point in worrying about the things you can’t change.