I largely agree with you that setting a target while investing in bitcoin is cool, but I don't prefer using timeframe to set a target in my accumulation because you might not be motivated to accumulate as much as possible, since you don't have a specific figure in mind, but if you have a target of accumulating like one Bitcoin or more in a specific timeframe, the enthusiasm and commitment will be there because he knows that he has to accumulate X unit of Bitcoin at a certain time, so their will be no room for complacency, and due to the fact that you has a target to meet, you will likely cut out any unnecessary expenses and channel that funds to your investment, so what am trying to say is that it is more better to set your target on achieving X number of btc at a certain time, than just investing with the intention of accumulating till a period of ten years thereabouts.
You are right a young investor should use a bitcoin target when accumulating bitcoin and not a time frame so that you can keep your bitcoin journey ongoing til you reach your bitcoin target irrespective of the number of years it takes you.
However, I think that it wouldn't be possible for any bitcoin investor to doesn’t have a strong financial strength to know the exact quantity of bitcoin that he can accumulate in a given period of time due to many reasons. Firstly, you are not certain of what bitcoin price will be tomorrow, next month, next year and the rest of years that you plan to be accumulating bitcoin and that will make you not have a specific quantity that you can be buying with a specific amount every week for ten years.
Secondly, our expenses and monthly needs amounts varies from month to months. Sometimes, you might have a higher expenses for that month which will reduce the amount of money for your discretionary income and other month it can be vice versa.
Lastly, we don't how our financial cash inflow will be like in future and if it will be enough for us to invest a lower amount of money than our initial planned amount due to constant inflation overtime. This is the reason why you must look for other means to increase your income so that you can also have a higher discretionary income to buy bitcoin and balance up with inflation.
Doing lumpsum give me this impression that we should wait for dip since we are thinking about buying large volume and spread it over time when we want to accumulate.
You don't understand the right meaning of lump sum and some people are thinking that you must lump sum in a dip which is not true. Lump sum means buying right away regardless of the price of bitcoin, either in the bull run or in the dip. Whenever, the money is available, you just buy bitcoin wit it.
For example, my regular weekly DCA is ongoing and I received a bonus of $200 at work, I can immediately use half of the money or all of it to buy bitcoin right away without considering the price of bitcoin at that moment. Lump sum is very effective when you are mixing it with your DCA.