With teachers in the UK facing a two-year pay freeze, most would grab the chance of a higher salary.
But in Mexico - where pay is already much lower - seven out of 10 teachers are refusing the chance to be evaluated for pay rises of 20 per cent to 150 per cent.
Some 779,000 primary and secondary teachers (67 per cent) avoided being evaluated on their academic and professional performance in 2010, out of a teacher population of 1,156,506, according to the Ministry of Education (SEP).
But only about 3,000 of those who showed interest won pay rises of up to 150 per cent as a result of their evaluations - despite the fact that these "successful" teachers scored only between one and four points out of a possible 20 in the segment that tests how effective teachers are in imparting learning to their students.
The procedure looks at each teacher's training history, courses taken, classroom performance, students' learning, the teacher's role in school, and participation in remedial programmes.
The education ministry's report showed that scores of between one and four points were obtained by teachers with doctorates or masters degrees and those who had taken professional postgraduate courses. Of those who submitted to the tests, 1,841 had doctorates and 42,338 had masters degrees.
It also showed that, among those evaluated, 3,702 were uncertificated. Yet they managed to score enough to win salary hikes, despite having had only primary or secondary schooling, or even less.
The programme of evaluation was one of the recommendations of the Organisation for Economic Co-operation and Development, following President Felipe Calderon's request for help.
In 2010, the education ministry allocated the national Union of Education Workers (SNTE) the equivalent of pound;18 million to finance the programme.
Mexico spends more per student than many nations that surpass it in educational achievement, but critics point to the all-powerful teaching unions that decide which teachers get jobs. Those graduating top of their class say they cannot get jobs if they do not belong to a union or if they do not make payments.
Following a recent revelation that neither the government nor many state administrations know how many teachers are on their payrolls, partial checks unearthed thousands of "teachers" who neither taught nor worked in any administrative role.
Perhaps this goes some way to accounting for why so few wanted to draw attention to themselves by applying for pay rises.