Usually I prefer simple investments because they are easy to grasp. In the past few years we saw many brokers promoting investments that were hard to catch. Those were complex investment schemes often structured in a complex way to confuse investors.
Some of these investment schemes were conceived on purpose with such a complexity in order not to let the potential investor understand its game rules. Obviously the only ones who earned from such a "business" were the promoters and the promoters only. In a complex investment scheme the promoter is required being always present. A simple investment instead is easily manageable by anyone.
That’s why I feel more comfortable in advising investors to approach easy investments.
I did both complex and simple investments. In the long term the complex ones demand higher legal expenses, lawyers, and mostly you need a certain amount of time in order to check that everything goes smooth. There are some investment categories whose value is easy to understand. Investments in the Real estate field are among the most popular. Obviously they have to be managed for good, but anyone will agree with me that buying an apartment is something easy that only need common sense.
Simple investments are easy and they keep going by themselves. Just like earth going around sun.