MATLAB: What is wrong with this code

Question

clc; clear variables;

x(1)=0;

tic

for i=1:500

x(i+1)=(x(i).^2)*0.5+4;

if abs((x(i+1)-x(i)))<=0.00000001

break

else

x(i)=x(i+1);

end

end

toc

Answer 1

 if abs((x(i+1)-x(i)))<=0.00000001

This condition is less likely to be met ... I think.