An answer to this question basically relies on two
factors:
1) traffic on your website - the bigger traffic, faster the
results.
2) maximum membership duration - amount of
time user will stay in your retargeting audience after
visiting your website.
For example: if your traffic is 500k visits per month and
your maximum membership duration across all used platforms
is 14 days. You can see the shift in performance after
approximately 21 day from the start. To se the full impact,
you have to wait, in this case, for 2 months from the
begining.
Wanna know why? Or looking for more
details? Feel free to
contact us and you'll get your answers.