I agree with all CEC2013's points, except this - it may be semantics, but I would say instead that some applicants have be refused because the VO is not convinced that the applicant has the required skilled work experience. (Can't be refused for wages, it is not a program criteria.) If the wage is not commensurate with the position, that may be one factor that the VO considers, but there will have to be something else - they will find a problem with the letter of employment, job duties/NOC, mismatch in terms of hours worked / salary received, etc., something else that challenges the credibility of the evidence you provide.