Note that I'm not saying you can't build strong trust, just that it's harder. You have to devote considerably more thought and intentional time to it. I say intentional time because when you're local to someone, you naturally build trust with them in every small interaction. In a remote setting, you need to create time and space for those interactions deliberately.
- Meet in person as much as possible, especially by bringing remote folks together for an extended (multi-day) trip. That encourages more informal in-person interaction. Plan specifically for non-scheduled time, non-working meals, etc.
- Have a regular one-on-one meeting with your reports, preferably weekly. Set up the structure to always have a planned topic portion and some small talk about life. Sometimes that'll be boring or painful, especially for techies. But the space it provides is extremely important.
- Communicate
- Communicate
- Communicate
- Seriously, the one thing that erodes trust more than any other is when people feel out of the loop or not consulted when others were. Document hallway conversations for remote folks. This is hard.
I'd recommend watching Andrei Rebrov (CTO & Co-founder at Scentbird) and David Tabachnikov (Co-CEO at ScholarshipOwl)