I just went through the process of interviewing with startups for a new job and my main takeaway is: most startups suck at interviewing.
Here are my top pieces of advice for startup founders hiring early employees:
1. Have a structure
At my startup we spent a bunch of time planning out the interviews ahead of time. Some may see this as time wasted, but it paid off when we started interviewing because there was no gray area. We had the number of interviews, the theme of the interviews and even questions prepared. Don’t just do more interviews to do them; have a structure and stick to it. If you need another call for a specific reason, then great! Do it! But if you just want to talk to the candidate more then it probably means they are not the right fit or you asked the wrong questions in the other interviews.
2. Communicate the structure
Be transparent with the interviewee regarding what the interview process is and how long it takes. This is an easy yet important step. You should communicate how many interviews, how long they are, and possibly even who they are with.
3. Be thoughtful about take-home challenges
Take home challenges are popular in startups, especially for engineering roles. I personally like them especially for junior engineers because it gives them a chance to show their skills instead of having to answer irrelevant algorithm questions in a technical interview. Make the challenge clear and concise. Make sure you aren't adding complex topics, let them focus on the coding and their ability to solve a tightly defined problem rather than their ability to learn new concepts in a short 3-5 hour period.
4. Understand where the candidate is in their process
This is tough and it becomes a bit of a game, but if they are getting other offers and you still have 2 interviews to go, you want to know that so you can either speed it up or turn them down now. You also want to make sure they are on a track to accept an offer, and if not, understand what you need to do for them to accept the offer.
Bonus: if you want to get a good understanding of a candidate then i highly recommend what we did at my company. After the screen and technical with their manager, we had a culture interview with all the founders in it. This was scheduled for 60 minutes and the candidate was told ahead of time to prep a 30 minute presentation on one of their passions. This was a great way to show their organization and presentation skills as well as gives some insight into their life outside of work. We found it to be the single best deciding factor once they passed the technical. The other 30 minutes were for questions around the presentation to drill deeper.