Today, every company is also a software company in some way or the other. Developers are the ones who are often tasked with pushing the envelope, helping you simulate, iterate and innovate faster than ever. Regardless of the industry your company is in or its size, hiring talented developers is critical for business to thrive. They are also in high demand, and not easily wooed by free passes or weekend retreats.
Best tech hires are typically the ones who are reluctant to come to your office or travel for an interview. They are critical resources at work and do not have time, energy or flexibility to take a day's leave and travel for an interview. They expect their prospective employers to understand that and proactively provide them convenience and flexibility. Online Assessment in person reduces the candidate reach again leading to missing out good candidates, as you will be restricted by geography.
A plain vanilla test is not be the best case to assess a programmer skills, you should rather do a code test in a real life code complexity scenario. Also just technical skill evaluation does not give a full picture of the candidate even for the purpose of screening, one needs to do all round evaluation on motivation, cultural fit and suitability using tools like video interview.