I can see a decline in my Facebook Logins. Why is this?

I can see a decline in my Facebook Logins. Why is this?

PoweredLocal has migrated away from Facebook as the primary login source after drastic changes they made in April. The login process for users has become extremely difficult, with up to 55% of users abandoning the login. They have also announced a degradation of data provided in the coming months, so in anticipation of this, we’ve moved to a solution that still allows the Facebook login but prioritises the form login. This is already showing better qualified data and an increase in successful logins by 22%. This would account for the low uptake of the Facebook login option you're seeing.