"Losing while learning" would be fine if low elo players were actually able to recognize where and why they made mistakes. If a mistake is not recognized as being a mistake, there will be no improvement. And since low elo players lack the game knowledge to identify what went wrong for them, they usually end up staying low elo whether they vs. high ranked players or not.
There's also the fact that high ranked players rarely, if ever offer advice to lower elo players while in-game. They usually just flame and shit-talk about how much better they are, if they speak at all. Because there's simply not enough time during the game to explain to a low elo player why a certain action is advisable. Do you really expect a diamond player to explain proper counter-jungling, lane matchups, how to farm well, when to trade, etc. all while a game is going on?
This in turn is also assuming the low elo player actually wants advice in the first place. Because many in low elo often misinterpret actual sound advice as flaming and criticism. Either that or they are simply unwilling to learn beyond what they already know, making advice pointless.
