After everything marketing campaign the best thing to do is to measure its outcome. This helps you know if it was a success, if you got returns on your investment and most importantly if it's worth doing again.
Unfortunately, I have to say measuring action taken by people who came into contact with your message can be a bit difficult.
This is because of different buyer personality and behaviour. Meaning due to these variables when you measure the outcome of your influencer marketing campaign, you are not guaranteed precise information or data.
Let's say, for example, you launched your influencer marketing campaign at around October. It did fairly well, to say the least. But the subsequent three months up to January marked a considerable increase in clicks, traffic, subscriptions, orders etc. Whatever you needed, these three brought in most of it.
Will you say the campaign was a failure if you measured the outcome at end of October?
Many mostly do.
But what leads to this unexpected results?
At the top of the list, is the butterfly effect. Little things have big effects. Don't underestimate the power of that share, view, retweet, mention and such like. Your next potential customers might see that and be interested so much that they visit your website. And just like that, they have already gotten into your sales funnel and its only time and, of course, your skills that will turn him into a customer.
Other factors are external variables, like the market conditions or even the weather.
But mostly it will depend on where the customer is in the buying cycle. The faster he moves in the buying cycle the better.
With saying all that. You can still measure the outcome. Some are more or less real time. Like views, likes, subscriptions, follows etc. These you can measure instantly and see if you reached your desired target.
Phone calls and registrations can also be measured. Same to orders and sales.
Needless say don't forget about the butterfly effect. Most marketing investments don't pay off instantly. They take some time. So don't trash your current marketing campaign for not being fruitful at the moment.
Engagement can also help predict the outcome. The more the engagement the more action you are guaranteed to receive because of your message.