The company has been happy with my performance these years, and I received RSU which started investing. I have never owned stocks before: even though the company is US-based, I'm not a US resident and I'm probably much more ignorant about the financial market than the average US employee. However, now I own stocks, thus I guess I cannot postpone learning the basics of stock management anymore. My main doubt is whether to keep these stocks after they vested, or to sell them. What should I look at, in order to make an informed choice?
Firstly, if I understand correctly, in order to make hold/sell decisions I should not look at the trend (performance?) of the stock with time, but at the return. This begs the question of what a return is. Since apparently, RSU don't grant dividend rights, the return should be the difference between the stock price when it vested, and the value today. Correct? PS before you ask, I did look for a definition of returns on this site, but I found this which clearly is not what I'm looking for (I didn't pay anything for my RSU, thus this ROI quantity cannot be computed).
Secondly, again if I'm not wrong, stock returns should be judged over a time frame of 10 or more years, not months or 1-2 years. In other words, if my first RSU batch vested two years ago, and now the stock price is lower than in 2017, this is not sufficient reason to keep. Equivalently, if the stock price is higher, this is not sufficient reason to sell. Is this correct?
Finally, does it make sense to look at these things? Or should I just sell everything as soon as it vests, and use the money to pay someone (a fund? a broker? I have no idea, I guess I should ask a new question then) to invest that money in a "diversified portfolio"? The rationale behind this choice would be that since I know very little about stocks, I don't have the means to make an informed decision on whether to keep them or not, and thus I should just pay a professional to take that decision for me. I'm located in Southern Europe, if that helps.
EDIT: the company is partly privately held, partly publicly traded, with a ratio between the two ownerships which may change later this year. If the exact ratio is of importance, I can close the question and reopen it later this year.