Hello I am an 18 year old guy and I faced this situation in my childhood.
I was quite poor in academics to be true very poor but this doesn't mean that I failed a particular year- I passed all my "final" exams, somehow! I used to get 38-45% during the unit tests and half yearly and somehow manage a 50 in the finals.
I mom, dad, brother tuition teacher everyone taught me but I never learnt the style of learning. Last night mug ups was my style. Everyone used to scold me for this. I even got beaten up sometimes, cried a lot thought to myself that I'll do well the next time but the next time was like the old times- just pass. I even boasted saying that I am the rank one holder in the failures I.e guys who failed in one subject are considered as failed so I used to fail in one or two and say I only flunked in one or two.
This kept going on for quite a long time.
Then came boards- class 10 exam.
Parents were shit scared. Even I was.
Got the same old marks in the unit tests as well as half yearly. Everyone gave up on me. They thought that I am going to fail for sure. Even I thought the same.
There were about 2 months left for board exam. I wasn't prepared at all but one day when I was having my afternoon sleep suddenly I heard a voice saying "you can do it timu- my nickname, believe in yourself, it's nothing related to the past sure you can judge a little from your past but not completely, the future is in your hands and you can ace the boards." I woke up after that shell-shocked.
After this incident some kind of superpower was instilled in me. I enjoyed studying and was pretty clear in my thoughts. I scored 88% in boards (ICSE) and since then I am continuously accelerating it.