Most people talk to more than one company if they're planning on leaving a job.
I'm not gonna sacrifice a whole day just to check whether the company's suitable.
The problem is that to get a good offer you need 2-3 competing offers. Assuming a 20% onsite success rate (from the article), thats 10-15 days... Most of us only get 10-15 PTO days a year, and wouldn't want to spend them in something harder than a regular day of work.
I usually interview with 3 or 4 companies when job hunting, and I would hate to have to spend a day at each.
I filter companies at the phone screen. Do you always go for an in-person if invited? I don't. I make sure to take at 15min of phone screen time for my own questions. (I don't do tech phone screens with recruiters -- complete waste of time. Competent companies have a tech phone screen with an engineer, who you can ask questions of.)
And I don't parallelize my job search. I do them serially, in priority order (based on pre-interview assessment), waiting 2 weeks after interview for an offer.
I get it that most people spray and pray, but for well qualified people this is the wrong approach.
This is why companies get away with silly whiteboarding and take home exercises. As a candidate, you have to be more selective than that.
Now that I am in New York, I don't generally even need to apply. I just wait for the recruiters to hit me up. When I do apply, I almost always get a response. I can be as selective as I want.
When I lived in Dallas (with only two years less experience than I have now) I might as well have been invisible. I took every onsite I got because I got so few phone screens to begin with. I couldn't afford to be selective.
As an aside, for an industry that claims there is a critical talent shortage this one sure has a bad habit of ignoring talent that isn't already local.
Stack Overflow would add several more. From a list of ~10 I can trim it down to 2 or 3 "I want to work there" companies.
A day is nothing for someone looking to leave a current position. Take a day off of work, what's the problem? Seriously. You're leaving anyway.
And then it's not like you can't just walk out on the interview at any time (say after the 2nd silly whiteboarding session) if you feel they are wasting your time.
The most important part of interviewing is the candidate's evaluation of the company. More time spent, and more people to talk to, is a fine tradeoff for a day of your time.
As a candidate, I don't really care what the company thinks they are getting out of a full day interview. I want this for my own reasons.