This is a good question. Here are a few points to consider.
First, there is a parallel passage in Matthew 25:14-30. It is the parable of the talents. So, if you want to compare the two, this is the passage to read.
Second, parables are not meant to be easy to understand, as they try to change a person's worldview. So, this parable is a bit tricky to interpret. The most difficult part of this passage is undoubtedly the punishment meted out to the servant with one mina. We might ask, "Was it that bad to give back what belonged to the master?"
Third, if we consider the above question, we get to the meaning of the parable. The point is that the master entrusted his servants to put the mina(s) to work. In other words, the express command of the master is for the servants to take risks and be good stewards of the minas. So, the servant who hid the one mina was directly going against the master's will.
Fourth, the theological point of the parable is that God wants his people to labor with the talents he has given them. If they refuse to labor, the people of God not only fail to realize what God wants them to do, but also go against his express wishes. In short, God's people must be good stewards.