How does your team record post event leads?

Tech services business here.. currently doing lots of conferences and making lots of connections. But realistically most of these connections get forgotten about.

I just sent a newish sales guy to an event, he comes back saying "it was ok, got a few potential leads". In my head, I'm thinking "ok, well wtf are they?".

Realistically, I need some kind of way to measure the events we spend money on. We use hubspot pro for a CRM, show in theory we should have no problem tracking every dollar we make to a specific event, ad, partner, or whatever.

But I'm curious how others are recording the leads they meet at events. I know it's just so easy to forget these, and forget to follow up, or push for a meeting.

I'm looking to build a real sales team, but hoping someone can shed some light on how they handle leads gathered from an event. Especially when they are rarely ready to buy.

Do you record every potential lead/partner/contact in a CRM? Is there anything you use to measure success, especially the success of salepeople who are being sent to events?