What is the significance of the phase angle? [duplicate]

I've the following circuit which gives an output of 1 with a phase angle of 3π/4. When we measure the circuit all we get is the state 1 (On actual QC, it's 90% of the time 1). Is the information about the phase angle lost by measuring the state? Could the phase angle also be part of the output?

OPENQASM 2.0;
include "qelib1.inc";

qreg q[1];
creg c[1];

u(pi/2,pi/2,0) q[0];
h q[0];
u(pi/2,pi/2,pi/2) q[0];
measure q[0] -> c[0];