My thoughts:
Subscription boxes are hard. I sold mine.
It's hard to keep subscribers happy every month, especially with food.
Most profitable subscription boxes are profitable because they are run by savvy internet marketers & capitalize on novelty, trends, & gifting, not because the products deliver incredible value to the customer.
I think Proactiv is the only subscription box service that's stood the test of time without having to drastically change their business model and they have historically been extremely savvy with their marketing.
If you look at the landscape of subscription boxes, it suggests that for longterm growth & profit:
1. Curation doesn't work.
2. You have to make / manufacture / private label your own stuff (Dollar Shave Club & Proactiv)
3. You should raise money, use that money to sell your first million boxes at a loss, grow rapidly and try to race towards an exit.
4. If your product doesn't solve a major problem (acne sucks, razors are too expensive etc), you are probably doomed over long term (10-20 year horizon), so it's best to sell in year 3-5.