Well, not exactly true...but it was almost everyone agreed that if you start with inferno / necro, the ladder climb and earning gold is much easier than other factions. This is only when you hit the 1k ELO though, that is when you are playing against other better people with better decks then you may want to do the same / improve your current deck.
I started out with inferno, but due to the fact that i got "lucky" with some necro cards, i changed when i hit the 1k elo point, and got stuck at ard 1.1~1.2k elo there due to the fact that i was missing some vital cards to move the deck further, but with the newly released expansion (forgotten wars), you are now able to buy specific cards much easier with no random rng involved.
If you stopped due to the fact that you can't get the cards you want, try playing now and check out the new system.
As for spending money, the devs at ubi are handing out free codes as well as some other sites that give you free seals, gold and packs as well, so it's pretty people friendly i would say. Besides, if you play often enough and level up, you get free seals and gold too.
Oh, and luck of the draw for both you and your opponent is quite important too, one wrong draw from you or a better situational draw from your opponent may cause you to lose the game, and vice versa. This is a card game though, so yea.
I picked Haven but later discovered how gawd dam boring that faction is, then I want to switch to Sanctuary to try out only to find that it cost so dam much to build a different deck, so I am stuck with a deck I don't like with no way to switch out.
Another reason is that there is no android version available, anytime I spent on my PC will be spent on playing MMO ang games I purchaded on Steam, so I just stopped playing the game and switched to Shadow Era instead.