Most of the time case sensitivity shouldn't be a constraint in these types of queries. The demo below accepts any form of "ready" (READY, ready, Ready, reaDY, etc).
response = '';
while ~strcmpi(response,'ready')
response = input('When you are ready to play please type "Ready": ','s');
end
If you truly only want to accept Ready and ready, use this condition instead,
while ~any(strcmp(response, {'Ready','ready'}))
Another form that gives the user feedback on their error,
instructions = 'When you are ready to play please type "Ready": ';
baseInstructions = instructions;
response = '';
while ~strcmpi(response,'ready')
response = input(instructions,'s');
instructions = sprintf('%s, (you typed "%s") ',baseInstructions, response);
end
Another idea since this is a binary task (the user types the correct word or they do not), why not use a question or message box?
qdh = questdlg('When you are ready to play, please press go!', 'Game', 'Go!','Go!');
You could also add a "Cancel" option.
