Question for those are PLG companies: What attribution model do you operate? Are there models better/worse suited to PLG motions?

Generally you want to track the progress of customer usage through the funnel. I think first click is the best model for making marketing budget decisions. It's also really important to find a north star usage event that happens early in the customer journey to optimize on. Like "first Trello board created", that kind of thing. For many PLG products if someone doesn't do a north star usage event of the product within 24 hours they never will. Over time you can see how each event the customers do early in their product journey correlates to usage in the future.

Great point on NS usage event. Wes Bush calls them value metrics and gives some great examples. E.g. For Slack, a PQL is when an account reaches its 2,000 message limit Going back to attribution, though, why is first touch better than last/linear/time-decay/position? Given how important virality is, a users first recorded touch probably isn't their first interaction, right?

For me its about what adds the most marginal value when deciding how to allocate scarce marketing resources. The earlier the touch recorded the more likely that touch wouldn't have happened without paid media/marketing effort. Once someone already knows you well all further ad touches could very well be not adding value, like branded search, etc.