With trading you should have a lot of knowledge for other coins and know which one to invest where and how much it would give you profit and in investing you just have to watch the one you invest grow or go low.
Yes I agree with you here is big difference between these two from trade you can get a daily profit and from investment you have to wait but both of them are profitable and it will help you financially I like investment as compare to trade because from investment I can get all my profit at one time and which can help me in target to achieve.
If you want to have a source of income which is more like being sure of profit then you should do both because if you are trading and if you want to have back ups then you should invest your money into something and they will give your profit that will serve as your back up source of income so if you will continue trading then you will earn profit daily and you still have a back up for the possible losses from trading that will be covered by your investment.