There is no only correct answer to this question. There are such people who believe that friendship at work is interfering. There are those who think the other way around. The organizations are also different. There are those where friendship between colleagues is not welcome, leaders believe that all forces should be spent solely on the performance of their official duties. And there are organizations in which friendship is encouraged, leaders are in solidarity with the opinion that an effective method of solving the problem in the friendly team will be able to find better.