It should be pretty obvious that Samsung (or even just Samsung Electronics) is a much larger company than HTC, with much more financial firepower. But it's interesting to look at some of the ways that scale affects things. Marketing is a good example.
Both companies disclose a 'sales and marketing' line. For Samsung this includes activities for the TV and domestic appliance divisions, but the way the spending has grown in recent years suggests that the great majority of the spending is for mobile - and of course the brand is the same anyway, so advertising for TVs will also bleed across to phones.
Where is this money going? Well, Samsung discloses a split in the 'sales and marketing' line - around 40% is advertising and the rest is 'sales promotion expenses' - a lot of which is sales commissions.
In Q4 2012 Samsung's budget was 13 times HTC's. Samsung hasn't disclosed the Q1 number yet, but if it dropped to, say, $2.5bn in Q1, the same proportionate shift as at the beginning of 2012, it would be about 19 times bigger. It's actually a little hard to see given the scale, but HTC's budget is down 40% year on year, to just $130m, a tiny amount. And given their operating profit was zero in Q1, they can't afford to spend much more.
In the handset market today, having a lovely product is necessary but insufficient. This chart ought to show why.
Incidentally, Apple doesn't break out a sales and marketing line (it only gives the advertising spend): in 2012 Apple spent about 25% as much as Samsung Electronics directly on advertising, some of which was obviously for iPads as well. However, it has contracts requiring mobile operators to spend money on advertising as well, so this isn't a direct comparison.