Also there's no point in bringing someone in for an interview before they've shown any coding experience. It's a colossal waste of time for everyone, including the candidate
We give an invite for a phone screen. It's just a chat so both candidate and interviewer can make sure that the job on offer and experience of the candidate match up. It's also a nice time for candidates to get a decent idea of what our company does so they can bow out if it's not really what they're looking for, which is good for everyone.
Then we send a tech test (take home). It's a simple challenge, with a lot of freedom. We give a guide time of ~90 minutes, but also let the candidates know that they can do more or less if they want. We ask the candidates to submit a written response as well, so they can explain if they're happy/unhappy with the test and their submission. Didn't have time to refactor as you wanted? Didn't write as many tests as you would usually do? That's fine, just let us know generally what you'd have done so we can take it into account when looking at it.
Then it's onto the face-to-face interviews etc.
The tech test segment is really enlightening. A lot of the time we can figure out a lot about the candidates ability to create software systems and communication skills just from the test. Most of the time, we spend a non-inconsequential amount of time looking at the test submissions. If a candidate was good enough to write it, we should take the time to really see what they did and review it. Sometimes we get really poor tests back, even from candidates we were enthusiastic about. Other times we get pleasantly surprised, with candidates who phone screened poorly smashing the test and giving a wonderful submission. I think it's immensely important to see what a candidate does with actually writing code. I also think it's important to make sure we see that prior to inviting them in, as they need to take time off of work, get to our offices and prepare for it. And even when we really want to progress with a candidate, the tech test gives us something to talk about to get to know the candidate better, and hopefully have a conversation that allows them to ask us questions as well.