Someone else was a better fit
Many candidates that go for interviews have the required qualifications and confidence, often making it a difficult pick for companies. The one that got the job, instead of you, may have had a quality that was not on the job’s requirement list. An example is ‘embracing change’, which fits in with the company’s flexibility.
Source: Daily Worth
You’re overqualified
According to Labour law, companies are not allowed to pay you lower than what your skills and qualifications warrant. If you are too good for the job, employers run the risk of paying you too little. They might not be prepared to adjust the hiring budget either.
Source: US News
Restructuring
Just like gardening, where you have to weed out the plants for their growth, a company has to do restructuring and rearrangement for that very result. Sometimes that involves weeding out, or eliminating positions that are no longer necessary. Unfortunately, yours might have been one of them.
Source: Daily Worth
They hired an insider
Sometimes the candidate who already has rapport or experience within the company will be a better culture fit. The chemistry will also be better as he/she would likely have formed relationships with the employer and colleagues.
Source: Huffington Post
Personal bias of management
Unfortunately, being well-qualified doesn’t always guarantee you the job. Some managers hire you based on whether they like you, or know you; hence the phrase: ‘It’s not always about what you know, but who you know’.
Source: H careers