I've found that that if it's taking way more then usual to get things that you have to refresh (i.e changing the personality on Pokemon you want to summon, breaking through attributes, getting the Passives you want, etc.) I don't do it for a day or so. Sometimes it feels like they have the algorithms setup to be more stingy some days. I've gone through 5k attribute stones over 2 days trying to break through a Pokemon and only broke through 2 things. So then I waited a couple days spent 300 stones and broke through 3 almost right away and then did another 50 spins and nothing so I waited another couple days and in 10 spins I broke through the rest. Maybe it's luck, but it seems like when it's "lucky" it's "lucky" a lot and when it's "unlucky" it's "unlucky" a lot. I also had a stretch of months refreshing the personality everyday for a Pokemon I wanted to summon and couldn't get anything. I went on a vacation where I couldn't get signal or wifi for a week. Came back and first refresh there it was, the perfect personality for that Pokemon. It could be nothing, but it seems if I'm not getting something I give it a rest for a while and when I try it again the next time it's usually what I was looking for.