I will suggest that if a person is merely buying anywhere between $10 per week/month and $100 per week/month is likely going to need way more than 10 years in order to get to a status of having had accumulated a sufficient amount of bitcoin. Perhaps such a person will need 20-30 years or more to really get to a decent place with his/her bitcoin stash.
For sure, each of us has differing expectations in regards to how much income that we might need to be able to live comfortably, whether we use bitcoin proceeds to completely replace any income that we have or to supplement income that we might have from other sources.
Bitcoin accumulation have to do with left over cash flow and at that not having sufficient steady monthly or weekly set aside founds let say $10 or even $20 which is way too much time to come up with a significant amount of bitcoin starsh, but then just as you said, sometimes we come across unexpected huge sum and if we are able to put all down on bitcoin it could cover up for a long period of time and a journey that surpose to take 10 years to 20 years could come much faster and easier.
The fact and most important thing is to have the determination to keep accumulating bitcoin along the lines and doing all that is possible to come up with an amount that can be valuable enough to generate good profits when the all time high happens.