As someone who screens a bunch of applications, absolutely I'll factor in a cover letter.
For me, the presence of a cover letter with half an attempt at customisation to the company and job ad demonstrates they actually care at least a little about this role at this company. And if it's well written then that demonstrates communication skills which I value highly in my colleagues.
It's really not often clear cut which one of two CVs is the "best qualified". The cover letter is just a bit more signal that will often swing my decision towards "let's take a punt".
People want to work somewhere to earn money. I assume you're one of those people that likes to ask "Why do you want to work here?". I'm sorry to burst your bubble, but unless you're a charity or doing something groundbreaking (e.g. SpaceX), the only reason people want to work for your company is money.
>demonstrates they actually care at least a little about this role at this company
But why does that matter to you other than ego? Barring some exceptionally unique work your company does, we know that the applicant wants to work there because you offer money for their particular skills. Why perpetuate a culture of bullshitting?
So in other words: if they have a good CV, they'll get through to the next stage regardless, but if they're a punt candidate then the cover letter might make a difference, maybe?
I would then ask: if I'm a punt candidate to begin with, the number of interviews I get is primarily a factor of how many applications I fire off into the crapshoot, right? What's the increase in success rate for applications with cover letters? Is it enough to outweigh the reduction in applications I can send from hand-crafting each of them?
For me, the presence of a cover letter with half an attempt at customisation to the company and job ad demonstrates they actually care at least a little about this role at this company. And if it's well written then that demonstrates communication skills which I value highly in my colleagues.
It's really not often clear cut which one of two CVs is the "best qualified". The cover letter is just a bit more signal that will often swing my decision towards "let's take a punt".