Mistake 1: Opening with "I am excited to apply"
This is the most common cover letter opener in existence. Recruiters have read it thousands of times. It says nothing about you, the role, or why the match makes sense — it just signals that you started writing without a plan.
The fix: Open with something specific. The company just launched a product, made an acquisition, or published research you found compelling? Lead with that. You worked on an adjacent problem at your last company? Start there. One specific sentence that couldn't appear in any other cover letter is worth more than a polished but empty opener.
Instead of: "I am excited to apply for the Product Manager role at Acme Corp."
Try: "I spent the last two years building the checkout flow at a fintech startup — Acme's expansion into embedded finance is exactly the direction I've been working toward."
Mistake 2: Summarizing your resume
A cover letter that lists your job history in paragraph form adds zero information — the recruiter has your resume in the same application. Restating it in prose form wastes their time and yours.
The fix: Pick one experience or achievement that maps directly to the biggest requirement in the job description. Go one level deeper than the resume bullet — explain why it's relevant, what you learned, or what the outcome meant. The cover letter's job is to connect a specific piece of your background to a specific need in the role.
Mistake 3: Writing about what the job would do for you
"This role would allow me to grow my skills in X" and "I've always wanted to work at a company focused on Y" are self-focused. The hiring manager is not evaluating your career goals — they're evaluating what you can do for them.
The fix: Every sentence should be oriented toward what you bring, not what you'd gain. "Why this company" should be about why you're the right person for their specific challenge, not why the job would benefit your career trajectory.
Mistake 4: Being vague about impact
"I helped improve our marketing performance" and "I contributed to the team's success" tell the recruiter nothing. Vague language suggests you either don't know your impact or are overstating a minor contribution.
The fix: Numbers when you have them, specifics when you don't. "Increased email open rates from 18% to 31% in Q3" is strong. If you don't have a number: "Rebuilt the email onboarding sequence — it became the primary driver of trial-to-paid conversions that quarter" gives a specific, concrete picture without fabricating a metric.
Mistake 5: Writing more than three paragraphs
Cover letters get longer when writers aren't sure what to cut. The result is a letter that buries the strongest points in filler and asks the recruiter to do extra work to find the relevant parts. They won't.
The fix: Three paragraphs, full stop. Hook and context (2–3 sentences). Relevant experience with a specific example (3–4 sentences). Why this company and a call to action (2–3 sentences). If a sentence doesn't do one of those jobs, delete it.
Using JobPilot to avoid these mistakes
JobPilot generates cover letters from your full resume and the complete job description — which already addresses mistakes 2 and 4, since the AI has specific material to work from. The areas that still need your attention are the opener (mistake 1), the framing (mistake 3), and length (mistake 5).
After generating, spend two minutes reading with these five mistakes in mind. Usually one or two need a quick rewrite. The structural work — matching your background to the role requirements — the AI handles well.