How do you move customers off social and onto your own store?
Give them something the platform cannot: earlier access, a restock alert, an order history that remembers them. A discount moves people once; a reason moves them permanently.
What decides it
The moment to ask is the order, not the follow. A buyer giving you an email address at checkout has already decided to trust you, which is the hardest part and it is already done.
The part that gets skipped
The follower count almost never matches the sales. Engagement in the comments is a far better signal than reach.
Short-form video is the cheapest reach available right now, which is exactly why it will not stay cheap.
Influencer spend works when the audience already buys that category, and burns money when it is chosen on follower count.
Where an app fits
The point of an app in this picture is ownership: social brings somebody once, and the app is where they come back to.