I'd like to add a quite entry here on complacency. I had a mathematics mock exam today and I assumed given that I do further and further pure mathematics I should be able to breeze through the exam without much prep. The issue was that it was not so easy, now the majority of the issues I faced were silly mistakes so not necessarily lack of knowledge but these slowed me down and put more time pressure on me. The mistakes occured becuase I wasn't putting as much effort into the questions as I deemed them easy.
The major problem occured when I topic came up which, during learning it, I skipped the exercises as it felt very similar to previously done topics. I then didn't revise this for the same reason assuming that I could quickly reason it out. The fact I had added a bit of time pressure meant that no I could not reason it out. So though I have not done badly in the test overall, I did get cocky and meant that I lost multiple marks which I shouldn't have.
Lesson learnt: Don't be complacent! Don't get cocky
I agree we all make mistakes and can't get perfect scores. For the revision I did and the situation I performed the best I could trying out the topic question to the best of my ability. I am not sniding myself for not doing well I am sniding myself for being arrogant. This ultimately led to me underperforming, it's the classic tortoise and the hare and tbh in most aspects of my life I am the hare.
There is also the fact that I may be reaching my limit in mathematics, there is stage for everyone where they reach their limit. If there were no limit everyone could put in the time and be excellent - which sometimes I falsely believe to be true but that's another issue. I'll see what the result is, tbh I am not so fussed about that as mocks are to see your holes and I can see a gaping one: my lack of respect for the difficulty in normal mathematics. I have a chance to redeem myself in normal mathematics on thursday, and in mathematics in general tomorrow. I have definitely spent some time today getting to know my weaknesses for tomorrow's exam.
As a note: I don't necessarily have a solution to not being complacent. I feel at the moment my complacency ties in with my laziness, and in a way the two are interlinked, and for laziness I do not have a solution. Though I am starting to realise that laziness is essential if used correctly, so I don't need a 'solution'. But complacency is never good, I guess the idea would be to know your ability in a field or at least gauge it against those around you. Importantly don't get swept up into their view of ability, keep in mind the overall populous. It's very hard to guage your ability which is why, I believe, many incredible people don't realise how incredible they are (in the context of everyone else) and why very mediocre people think they are incredible.
Anyway, stay healthy.