I always hear that the top student take the STEM subjects. So I was wondering:
1.Why do the top students decide to take the STEM subjects?
2. Why are STEM subjects so important? What sort of skills to you gain after taking those subjects?
3. How valuable is the BSc compared to a BCom or BA?
4. Are top banking/management consulting companies recruiting those who take STEM subjects? If so why?
Moderator’s Edit: STEM = Science, Technology, Engineering and Mathematics
Hey! I’m a fairly STEM orientated person, with a few other interests, so I hope I’m qualified to answer 
1 and 2: While I’m not sure that ‘Top Students’ take STEM primarily, there are a huge number of reasons to do so. STEM gives a great breadth of possible jobs in the future, is intellectually rigourous and thus stimulating, and trains the mind well for the changing world that we face in the future. What I mean by this is that in an age of technology, particularly the engineering strand prepares students well for a rapidly changing working environment where jobs will likely evolve throughout our lifetimes. The engineering way of thinking prepares students to write well, structure critical arguments and find creative solutions. I personally believe that the days of working one job for your entire life are gone, and engineering is a path that allows you to work in a huge number of different areas throughout your career, because of the critical thinking skills.
Science and mathematics are similarly valuable. I’m not so sure about pure maths for most people, but certainly science is an area which I believe will exist for awhile. Doing an engineering course is something I’d recommend for most people, in a conjoint.
3: This probably depends on what Uni you’re at and what field you’re entering. I’d say none of those are hugely valuable by themselves - your masters is really what will differentiate you, unless you go to a really top tier school where people will be interested in you because of that. For instance, a BS (equivalent to a BSc) at HYPSM would allow entry into top technology firms, and a BA in Econ would allow entry (to a basic role level) into top economics firms, but you really need your Masters to rise to a meaningful role.
4: Top management consulting firms aggressively recruit engineering students, because of what I described in my first point (my uncle went through exactly this process). The critical thinking skillset is invaluable, the entrance into and subsequent completion of the degree proves capability to deal with some level of academic rigour, and the ability to write reports in a cohesive and concise manner is super important.
Why?
Your mind is your biggest asset and it only develops if you continue to work hard to train it, learn new things, force yourself to confront rigorous problems and focus on self-improvement.
Additionally, the world is a competitive place and the “hardest” problems are the ones that demand the most intelligent and resourceful people. Among many reasons why investment banking, working at SpaceX, getting into Harvard, working for a hedge fund and becoming a Prime Minister are considered to be impressive is because it is simply so “hard” to achieve that the number of people that can do is very low and so the “market value” placed on doing these things is very high.
How does this translate to taking STEM?
In general, Mathematics, Biology, Chemistry and Physics are viewed as being the most difficult high school subjects in many instances. This is why, many students, who don’t necessarily know they like them, take them anyway because it’s a good bet to do the hardest subjects possible in the absence of other strong reasons.
In high school, I wasn’t sure what I wanted to do but I took A Level Biology, Chemistry, Mathematics, Further Mathematics and Physics because they were the most rigorous subjects available. While I enjoyed Business Studies, Economics and French, I wouldn’t have taken them as primary subjects without my core foundation of STEM. (note: A Level French is actually fairly challenging)
Here’s one example: Marketing.
Ever watched Mad Men? Marketing used to be about fashionable folks who probably haven’t done math in a long time thinking of trendy ideas based purely of their subjective whims and “intuition”. Today, Digital Marketing has become extremely quantitative and Return-on-Investment focused with nearly all marketing channels being trackable. A new breed of talent has entered the marketing space who are very quantitative and allocate marketing budget like a stock analyst would allocate capital between equity positions.
Here’s another example: Finance
In Finance, algorithmic and high-frequency trading relying heavily on mathematics and statistics has seen a euphoric rise to glory over more qualitative, discretionary forms of trading in the last 10-20 years and firms like Citadel, DE Shaw and Renaissance Technologies have risen to prominence. Quantitative minded thinkers from STEM backgrounds are best equipped to deal with heavy number crunching in financial analysis which often becomes more a question of statistics and game theory than fundamental research in “quant” hedge funds.
This trend is only likely to increase and continue to push prominence into computer science, engineering, statistics, data science etc over fields like law.
BCom (Bachelor of Commerce) degrees primarily exist in New Zealand and Australia. Although none of these degrees at most of the New Zealand and Australian universities are very selective, BSc (Bachelor of Science) degrees tend to have a higher rank score minimum/ATAR cut-off etc and thus on average attract a higher calibre of talent. The pre-requisites for a BA or a BCom are normally much easier to achieve and if you assume a degree’s market value is roughly correlated to the average calibre of the people taking it, a BSc which is usually harder will generally have a higher market value. While a BCom is generally more practical, many of the core skills of business like accounting and finance are very easy to pick up for an intelligent mind - this is why so many Ivy League graduates are hired on Wall Street despite having no formal finance or accounting training.
Yes, STEM candidates are currently winning jobs at investment banking, management consulting, technology and Business Schools with much better odds than candidates from humanities backgrounds in general. This doesn’t mean you should just blindly do STEM but it is empirically true that these firms take more STEM graduates because STEM graduates are on average smarter, from harder degrees with better quantitative reasoning skills.
p.s. I absolutely love humanities subjects and in high school English was my best subject over Maths or any Sciences (I scored a number of Top in the Worlds in CIE English). When I went to Harvard, I did both my undergraduate and masters degrees focusing on Applied Mathematics-Economics primarily because I loved the coursework so much but also because it made more career sense than pursuing sociology etc given my interest in finance, consulting and tech entrepreneurship.