Landing an interview but not getting a job offer can be crushing.

In many cases, the person being interviewed thinks things went well, and maybe they did. Perhaps the interviewer or interviewers seemed excited to see you, and maybe you felt you came in with the right questions to ask while also answering their queries well.

Sometimes, of course, anyone can just be beaten out for a job. You might even be the best candidate and lose out to an internal person with better connections or even to someone willing to work for less money. In most cases you'll never know what happened, but it's important to consider ways you can improve to better your chances for next time.

The points our Foolish investors will look at here aren't the only reasons people lose out on jobs, but they are three of the biggest. The first one addresses that while many people think they did well in an interview, perhaps they need to be a little more critical of their performance.

A woman begins a job interview by shaking hands

Interviewing can be tricky but there are ways to get better at it. Image source: Getty Images.

Interviewing poorly

Selena Maranjian: One thing that keeps many people from getting a job they really want is when they interview poorly. There are lots of things that can go wrong in a job interview.

You might, for example, arrive late and be inappropriately dressed. Your handshake might be weak and you might not be making full eye contact because you're nervous. You might be so busy thinking of what you want to say that you don't fully listen to the questions you're asked. 

Many people don't sufficiently research the company or the job before arriving at their interview. That can show, and it can hurt you. You want to impress the interviewers with how much you know about the company -- such as its achievements, its latest initiatives, its competitors, its strengths, and its risks and challenges. You want to convey that you know what the job entails -- and you're the perfect fit for it.

Be sure to ask questions, too. You might, for example, ask about how the job is structured, who you'll report to, what the employer sees as the most important skills needed for the job, and what he or she sees as the position's greatest challenges. It's usually good to not discuss salary at a first interview, as it can seem that you're more interested in that than in the job opening. 

You can leverage the interview further by sending a thank-you note, perhaps including an article or study you mentioned during the interview. Above all, remember that the interviewer needs to be able to imagine you in the position and doing well in it -- so during the interview, make it clear how perfect you are for the job. If possible, demonstrate that -- by showing how you'd work on solving a company problem or by offering a press release you'd write for the company -- whatever the job involves.

Not having enough confidence

Maurie Backman: Sometimes, landing a job is all about presentation. If you come across as self-assured and knowledgeable in your field, you're more likely to get hired than someone who's wishy-washy about his or her skills. That's why it pays to approach each interview you attend with confidence -- even if the role you're applying to is somewhat of a reach.

In fact, when I was first applying for finance jobs right out of college, I didn't have a ton of experience, and I let that be known during one of the early interviews I attended.

Later, when the recruiter I was working with informed me that I hadn't been chosen for the job, she said she'd gotten good feedback about my skills and qualifications. The problem was that I'd come off a bit too timid during the interview, and the company ultimately decided to go with a candidate who had more of a "can-do" attitude.

Even if you're fresh out of college with limited expertise, go into your interviews feeling good about what you can bring to the table. The more confidence you exude, the more desirable a hire you'll be.

Asking for too much

Daniel B. Kline: In certain high-demand fields, it's possible to be very demanding when it comes to salary, perks, and benefits. If you know the company interviewing you has a very limited pool of candidates to choose from, then you may have the upper hand and can be aggressive in negotiating.

In most situations, though, that's not the case, and trying to get too much puts job-seekers in a difficult position. You don't want to ask for too little and leave money or other benefits on the table. But you also don't want to price yourself out of the job or come off as demanding or difficult to work with.

The clear way to avoid that problem is research. Use websites such as Glassdoor that show what other people at the company make. Even if it's a smaller business not listed on sites that aggregate salary info, it's still possible to determine what general salary ranges are for that type of position. It's also easy to find comments or other anecdotal evidence about some companies as to whether you can deviate from the standard on benefits, such as paid time off.

Making yourself the most expensive candidate who asks for special consideration in numerous areas could open the door for the company to hire someone cheaper. The company make like you best, but it may also like the second choice enough to not be willing to pay more for you.

Don't short-change yourself or take a job for less than it should pay or less than you're worth. At the same time, don't try to get every dime, every perk, and anything else you can think of, because it may well backfire on you.