Why Did Cloud Not Make Soldier?

All SOLDIERs are showered in Mako and injected with Jenova cells. It's why part of the requirement for being a SOLDIER is a strong sense of self - and the reason Cloud was rejected. Hojo's experiment was to perform the SOLDIER treatment on people who were NOT fit to be SOLDIERs.

Why did Cloud stop being a SOLDIER?

Cloud hid his identity from the townspeople, ashamed of his failure to join SOLDIER, though he did visit his mother who asked about his new life with Shinra. Cloud defeats Sephiroth in Crisis Core.

Is Cloud Strife not a SOLDIER?

It is revealed that Cloud never qualified for SOLDIER, and instead enlisted as an infantryman in Shinra's army. During the mission to Nibelheim, Cloud served under Sephiroth and Zack, hiding his identity from the townspeople out of embarrassment. Following Sephiroth's defeat of Zack at the Mt.