Play enough solo and you'll realize how literal players take the "solo" in solo queue.
If you read enough salt in dedicated places, you'll find the same pattern. Players who think they already know it all, and head into the ranked modes already thinking they're the MVP of the team, and as such, either get too careless, rush in, and lose all the fights, or push too soon, or not at all, because that's "not my job" and go for splats instead - so they push far into enemy territory, trying to rack up those sweet kills, while the RM on the other side of the map is about to get dunked. They also tend to have a severe phobia of the "ouch" button, so if their icon gets crossed out, assume there's at least one player waiting to take you out next.
Then there's those who try to take control of the team whenever. You'll notice them spamming "This way" far too often, whenever they spot an enemy, whenever they don't have to do anything else, if you see that squid, you'll have a hard time focusing. Luckily, I don't see the over-communicators around much.
And then there's the savior. That one squid who has amazing chemistry with you, moves according to player advantage, and "boo-yah!"s you whenever you help take down enemies that were blocking their path, or help take the lead (back). You want this kind of player on your party, you want players who actually try to make teamwork happen, and understood that even in "solo" queue, you end up on a TEAM of four players, and need to communicate and work as a team, even with the little communication options that are available. They lose a fight and notice the enemy going to shark? They say "ouch" twice to warn us. If only people listened.
Some players will fall back a little when there's a 2v3, or 3v4, or even player count-fight going on, so it's safe to superjump back into action. If you see these players, make a mental note to thank them later. They're not being cowardly, they are trying to reel back in as many players as they can before returning to the fight (most likely I suppose. I assume the better).
But at the end of the day, solo ranked modes are a mixed bag. You don't know what types of player personalities (and comps) you're being dealt beforehand, and you gotta try and make the best out of it. Always try to learn from your ranked experiences, so you don't fall into the same pitfall most solo Q warriors fall into - and make sure to learn different weapon's roles, strengths, and weaknesses - and learn to judge when it's safe to push, and learn different routes you can take when returning, or pushing farther too.
Play as if you got nothing to lose (but don't get too careless either). While it's frustrating to get cracks or maintain, or even de-rank - if you always play with the possibility of LOSING more than just that one match, every match, you'll just stress yourself out, and have an overall worse experience.
(Edit: Whoops, didn't notice I used the strikethrough BB code wrong again. Cursed be my lame brain)