look at it with the same ACL-logic as always:
0: match the bit in the address-part
1: don't match the bit in the address-part
This ACE doesn't care what is in the first, second and third octet, but matches on the "0" in the forth octet. As this is rarely useful, I would assume that it just was a misconfiguration, that resulted from the try to allow a particular /24 network where accidentally a subnet-mask was configured instead of a wildcard-mask:
e881(config)#access-list 100 permit ip 172.16.10.0 255.255.255.0 any
e881(config)#do sh access-list 100
Extended IP access list 100
10 permit ip 0.0.0.0 255.255.255.0 any
e881(config)#