Hey Bastian,
Your questions are very logical, and this is a big topic…so I am glad that you started it.
Well, many factors will not allow you to go gradually with your plan all the time.
For example, if you have issues with computers, VPS, and the internet. Somethings small things might cause unexpected results.
Also, we are humans, so quite often, we make mistakes for any reason. The one I remember the most is one trader complained that he fell asleep with the tablet in hands. All night rolling around, he opened and closed many positions… :) I know this won’t happen to you, but yes, it happens that we make some mistakes. This is why it is very important to deal with EAs and trading in general when you are very fresh and not tired.
Another thing, I would suggest you is always to withdraw some of your profit for something nice…family, vacations, improve your standard of life. Invest in some business or anything that will diversify your income even more.
A lot of traders make profits, and they never withdraw. Just increasing the account doesn’t make sense if you don’t enjoy in some way.
For example, I always withdraw 20% of the profit…but that is a personal choice, of course.