The reading challenge is a good idea with a failure mode built in. Counting books rewards short ones, finishing rewards stubbornness, and the streak rewards anxiety. Here is what works instead.
Why the counter stops helping
A number changes what you pick. Once the goal is fifty books, a 900-page novel becomes a bad investment and a 120-page one becomes a good one. That is a strange way to choose what to read.
The streak problem
Streaks convert a pleasure into an obligation, and an obligation you break once tends to stay broken. The day you miss is the day the whole structure stops working.
Fix the slot, not the total
Twenty minutes at a fixed time beats an hour whenever you get round to it. The slot is what turns reading into a habit; the total is just the receipt.
Abandon books freely
Fifty pages, then decide. Finishing a book you dislike costs you the four you would have enjoyed instead. Nobody is marking this.
Keep one sentence, not a rating
A star rating tells you nothing a year later. One sentence about what the book did to you is a note you will actually reread — and it makes you pay attention while reading, which is the real gain.
Read where your phone is not
The single highest-leverage change most people can make is putting the phone in another room. Not on silent. Another room.