I don't see what you mean by increase in salary, seeing as the candidate's language skills are clarified at the point of hiring. If you hire Pablo because he speaks Spanish, why should he expect a raise for speaking Spanish 6 months down the line?
Salary increases aside, there is a significant number of white collar jobs in London that are only open to people who speak English plus X language.
I don't see what you mean by increase in salary, seeing as the candidate's language skills are clarified at the point of hiring. If you hire Pablo because he speaks Spanish, why should he expect a raise for speaking Spanish 6 months down the line?
Salary increases aside, there is a significant number of white collar jobs in London that are only open to people who speak English plus X language.