Personally, if you've already dedicated 4 years to your PhD and have collected all your data so only a write-up remains, it would be a waste to quit your PhD. You should look to the resources provided by your university for help in writing if you're struggling. My university has regular classes for effectively reading and writing, at different stages fo your PhD which are supposedly very helpful. Also, it is common for people to feel lethargic when they're writing up results; i think thats common across all industries as well as academia. . With regards to the reading aspect, there are techniques people have posted online which worked for them worth looking at. Even more, since you already have the data (and possibly conclusions), the reading may be a lot easier than you think because it will be focused.

The nature of the world these days, a PhD will mostly add something to your career. The "job" you may have been able to attain without your PhD, maybe easier to attain now that you have one (this maybe a moot point when you're only a year into a PhD, but should be an important consideration when you're 4 years in). Slowly but surely, a wider acceptance of the "special skills" that PhDs possess is being recognised. Besides, it leaves the door open for a future return to academia should you seek it.

TLDR; Look for help within your college for writing and reading (subscribe to a course). Speak to your college careers team about possible career paths with a PhD. Form a goal and work towards that rather than the completion of your PhD (which will become a milestone instead of the end). Take a break, form an ultimatum for yourself, and attack.

I would love to offer advice for quitting, but i feel it would be reckless of me. I am finding it hard to deal with the regret over leaving behind a year of work; i cant even imagine the burden of leaving behind 4 when the end is so near.

Maybe you're right. I've never personally felt inferior, although i studied at the same institute at the Masters level. I've spoken to other PhD students, and they dont seem to have the same issues as me, but that is just a few people.

Regardless, another factor that's really playing on my mind is that I can no longer see an end goal. Initially, i imagined a career in academia, but now i dont want to walk that path. I'm struggling to see a result of the PhD, that will take me somewhere that i could not have reached without it.

2) Before starting, I had the usual scenes of smiles, respect and reverence play out in my head as i proudly sit with my PhD. I also wanted to be a researcher in the future and eventually a lecturer. Being in the environment, i no longer care for that dream and can't imagine spending the rest of my life in academia. It just seems dull, constantly stressful and uninteresting. I feel like there are other jobs, I'd be much happier in and that are more lucrative. This in turn has made me lethargic, disinterested in my work, and depressed. I feel like everything im doing is pointless and all for show.

3) I have done an extensive literature review and come up with a plan for the work, which sounds reasonable. However, I have a feeling deep down, that my questions are useless and too abstract. Like im trying to be too clever and sophisticated. Furthermore, I have suggested that i am going to do some complicated modelling, which I currently dont have the abilities nor skills for, and am so afraid that I wont be able to do it.

I'm hesitant to leave because of all the effort I've already put in, and the reality that the work will be just be discarded. I've got a good job lined up for the autumn (not the best i feel like i could secure but good, as I applied when all schemes were full) should I quit, so i wont be out doing nothing. I've contemplated remaining on to obtain an MPhil as it may prove useful in securing other prestiguous jobs in the future, but i would have to dedicate another year to this because i havent done any actual data collection as of now. I feel like dedicating another year which will undoubtedly be mighty stressful, will just leave me further unfulfilled and am unsure whether the extra time to possibly securing an MPhil will be even worth it. For context, I am hoping to go into a consulting career.

Any advice, welcome

For context, I am currently studying in one of the best universities in the UK and probably the best department for what I am studying.

I am about a year into my fully-funded PhD and am coming up to my yearly review, similar to a MPhil to PhD transfer exam.

For the last 6 months, I have felt an urge to quit for various reasons:

1) A sense of inadequacy and being in over my head. My project is very interdisciplinary, trying to incorporate ideas from other disciplines into my field. However, I am not acquainted with the other disciplines, nor is my supervisor, nor is anyone in the department. Also, I dont feel like I even have the requisite technical ability in my own field. I intially chose this topic because it was something i found intersting but never had the chance to study before, and that i could pick up the technical skills on the way. I feel like i overestimated my own abilties, the volume of literature to cover is overwhelming, and theres always something else I've missed when I'm forming my research questions. Disappointingly, theres no one to tell me so and I often find myself finding out later when an article pops up. I am so fearful that what i am doing, may not be unique enough without me knowing, after I dedicate so much effort to it. On top of it all, i don't really love my topic either. I find it okay.