Adding to the straws by @Tunnelthug and @GetSmart...the 4Q FY21 result was impressive, but it seems the market was expecting more.

James Mickleboro from The Motley Fool pointed out that while quarterly revenue increased by 104% (year on year) to $129.9 million, it was only up 13% since the end of March. Investors seem to be concerned that revenue growth might be slowing. 

Analysts are expecting ZIP to grow earnings at 80% per year over the next 3 years (see the SWS chart below). The concern is that if growth continues as it has in the last quarter, the yearly growth will be lower than expected (50-60%). Lower revenue growth impacts both the future earnings and the multiple used to value the business.

To maintain current valuations, revenue needs to increase by 20% this quarter. This would get revenue growth back on track at 80% year on year.

Disc: hold shares RL

Peter Switzer weighs up whether to sell or buy APT and ZIP in Switzer Daily

He concludes "that banks and their credit cards are simply not liked by young people, who are the future. I’m sticking with my Zip stocks and could buy more if the price falls significantly from here."