Normally when on holiday, I pick out a pacy thriller to read. I never truly escape the pull of political Twitter spats, or my growing inbox, but I do try to switch off from Westminster for a week. However I am useless at saying no, so when I was asked if I would review Isabel Hardman’s Why We Get the Wrong Politicians I agreed, reasoning that at least I would actually have some time to read it, even if it was essentially a book about the thing I was seeking solace from.

I am not a reader of overtly political books. When I have tried in the past, as part of an exercise in keeping up with the Joneses or some stupid belief that if I hadn’t read Alan Clark’s diaries I would be less good at my job, I found that they are usually either overly cerebral – to the point of self-aggrandisement – or needlessly cynical. Hardman’s book is neither.

It is easy to read and easy to understand, especially considering the fact that it covers some of the fiddly, complicated and frankly unbelievable ways in which our political system works. As a Westminster bubble dweller it is hard for me to be a proper judge of how accessible it is for less politics-focused readers, but I think it would give anyone a better understanding of both the benefits and pitfalls of our legislature.

The book is neither a defence nor a criticism of how politicians behave, and its tone is almost jarringly reasonable in these times of pearl-clutching, hero worship and searing hatred. Hardman, who is a political journalist and the assistant editor of the Spectator, aims to use the book not to highlight terrible politicians, although I know that must have been tempting. Nor does she seek to beatify those she thinks are good, although the Conservative MP Charles Walker is clearly a favourite (deservedly so). She seeks instead to look at how and why our politics forces politicians to be good or bad.

The strongest part of the book is its discussion of how politicians get selected as candidates and then elected to parliament. The author, unlike the political establishment, seems to have taken the time to listen to candidates who were not elected. Having been a candidate I know how maddening it is that you seem to be pulling a huge amount of weight at significant personal and financial cost and yet are ostensibly treated like a child who needs to be kept in the dark about the hushed conversations of the adults. Or that you have to take verbatim instructions from on high, even if on high hasn’t got the faintest idea about your local area, and doesn’t understand that overlaying London messages outside of the capital will never help anyone. Candidates who win, it seems, continue to play out this childlike role, desperately seeking the approval of the parent and teacher, rather than being the critical friend that political elites actually need.

Most political analysis starts with the fully formed politician, without attempting to understand how the men and women who represent us were groomed before they walk into the Palace of Westminster. Hardman gives this aspect the time it deserves, casting new light on why politicians end up in two categories: “yes men”, used to spending their time doing ridiculous tasks to prove themselves, or difficult backbenchers with pet projects (with the former greatly outnumbering the latter).

The book goes on to look at how political patronage, parliamentary one-upmanship and the system for passing bills into laws – through limited debate, faux scrutiny in a public bill committee and strong-arming House of Lords amendments – is creating rubbish legislation. She discusses some of that legislation in detail: her heart, in this book and in her journalism, clearly lies in housing policy. She uses examples such as the spare room subsidy (bedroom tax) legislation to show how unintended – or, in fact, intended – consequences of reforms were not properly thought through.

Worse than this are the areas she highlights that get no thought and no legislation, such as the woeful state of policy about temporary accommodation for people awaiting housing. Hardman manages to enter the debate thoughtfully and without a partisan air. She provides detailed yet readable scrutiny of these policies and their outcomes, and exemplifies how a cool head with an understanding for a topic might offer useful critique – something that, glaringly, did not happen before these policies were left to detrimentally affect millions of lives.

There is a huge amount written these days about the lack of diversity in parliament, usually focusing on race, gender and class. Hardman includes some of this. However, her focus is on how the experiences and peer groups of politicians and civil servants lead them to make mistakes. Hardman theorises that even those who come from working-class backgrounds are, by the time they end up in parliament, fairly distant from the realities of tax credits, temporary accommodation and fire safety in tower blocks.

I think she is right. A politician from a pit community or raised by a single parent is, pleasingly, no longer that uncommon. However, those who make it to Westminster are likely to be somewhat distanced, in both their friendship groups and lived experience, from most of their constituents.

I found some of this analysis hard to read and I wanted to reject it, as if desperately clinging to my “real person” status. Hardman argues that few politicians would have friends or family in temporary accommodation or living in council blocks, or would have understood how important tax credits were to a family income. I felt myself bristle at this as I received tax credits only a year or so before I entered Westminster – during the debates in parliament about the cuts to this benefit I remember feeling that some contributions were actually insulting about me. Similarly, I was paying off my student loan for the first two years of my term in parliament and would chuckle as some MPs talked about people with student loans as if they were “other”.

I have a brother who lives in a council block, who has also lived in some of the worst temporary accommodation known to man. I have family who live on disability benefits and nephews who would be destitute were it not for the benefits system. But I had to conclude while I sat on my holiday in France (admittedly in a caravan with my mates who are builders and midwives) that even I, having only been elected for a few years, no longer felt anywhere near the same effect of changing or failing government policy. I’m not willing to admit that I’m fully in the Westminster bubble, but when government really messes stuff up or (as in my case with Labour’s free nursery and tax credits) really improves things, I am insulated from its effects in a way I never was before.

My window into this world is now through my constituents and the surgeries and casework I do for them. One of the charms of this book is the view into that side of an MP’s job, with some cracking anecdotes about visitors to David Cameron’s surgery while he was prime minister – including the solicitor who explained to him in precise detail how bad his changes to legal aid were (Cameron subsequently asked Michael Gove, then justice secretary, to change the system). I have constituents who come from all over the world and many of them cannot believe that they can just walk into my office and chat with me, or that I don’t drive past their homes in an armoured SUV but instead knock on doors with a clipboard.

Although Hardman cites many politicians bemoaning their lot as resembling that of a social worker, I think it is the most enjoyable and most vital part of my job – for the very reason that six hours in a damp church hall, talking about everything from broken slabs to family members imprisoned abroad, pops any Westminster bubble. This book is one of the best accounts I have ever read about MPs’ constituency duties and, without indulging in hero-worship, it does a really good job of humanising politicians and their constituents.

I would be lying if I said that the book didn’t depress me a little, as it punctures very accurate holes in the job I dedicate my life to. For example, I was left feeling a little deflated about the scrutiny I and others try to perform on bill committees, which leads to zero change in the legislation. It does highlight all the work done in private meetings – that no one ever sees, but that helps humble backbenchers such as me improve things – but it (rightly) made me feel that there was still a huge mountain to climb.

I knew this, of course, before reading the book. I knew I probably made a greater difference working in a women’s refuge. I hear myself saying every day, “This is a crazy way to try to run a country”, but somehow I still believe change is possible. Why We Get the Wrong Politicians suggests some very practical improvements, especially around candidate selection, though I know they will almost certainly never happen.

Hardman is not one of the gregarious members of the lobby who are always at the bar, backslapping politicians. She is a listener: she has a gentle approach in her dealings with politicians and the Palace of Westminster and we trust her. That makes this book an honest and accurate appraisal of my workplace.

It might not have been a pacy thriller, but there is sex, love, scandal, tortured souls and obsessive characters, hopes, dreams and heartbreak in this book. Yes, it is layered with discussion of fire safety regulations and policy about cones on the motorway, but nonetheless Hardman’s book is a vital and compelling read for anyone interested in the way our politics does or doesn’t work .

Isabel Hardman, David Runciman and Jason Cowley will discuss “The Condition of England” at Cambridge Literary Festival on 24 November

Why We Get the Wrong Politicians

Isabel Hardman

Atlantic, 307pp, £18.99