if you are a person who has assets everywhere and is not able to manage them all, yes to me you can. it is very good for you to leave it to the manager. but for those who only have standard wealth and are able to manage themselves for me there is no need to bother paying their salaries. never be lazy, because the purpose of work is to make ends meet.
That is the thing, money managers do not work for free, and after all why should they, right? However the more costs you add to whatever investment strategy that you are using the smaller the profits you could get, this is why the richest persons alive do not really use a money manager and do all their investment decisions by themselves, this means that it is imperative that we learn how to do that ourselves as well, as not only it will increase our profits over the long term but it will reduce our costs as well, which is just as important.
This is needed one for people who hold funds atleast in millions. For common people who hold small volume of investments there is no need of fund manager in my view. Everything is a learning, the small experience gained out of our own experience could make thyself a fund manager. The market is in need of potential people, and fund managers mostly accept certain percentage of profiting apart from the salary.