Why is map visibility so important?

I have noticed that a few different commentaries they say that the reason a team lost their match up was because they didn't have enough visibility of the map. Is it truly that important to see the whole map?

Can you tell me what roles are supposed to do the warding and when and how they go about it?

Solution 1:

Apply it to real world and you'll immediately see the benefits of map visibility. How well would we be equipped for war without radars? How valuable is stealth warfare etc?

Being able to sneak up on opponents is too strong of advantage to let any team have for free. Wards allow you to prepare for incoming ganks, to move quickly on map objectives, and even for some champions provides as a way for escapes.

The most obvious understanding of this comes to bottom lane. As a support, your job is to let you carry farm as much as humanly possible without being interrupted. Wards allow you to watch for incoming jungle ganks, roamers, etc.

The other role whose main job, among clearing neutral minion camps, is warding, would be the Jungler. As the bottom lane support is, quite frankly, stuck at bot lane, the roaming Jungler has a better chance of passing through areas that could use wards that would make or break a game. Until lane phase is over and the support starts to move around, it is important for the Jungler to ward the rivers to prevent ganks on top and mid, attempts on dragon and baron, counter jungling attempts by the enemy, as well as to provide constant vision of the other team so that your own knows when it is safe to pursue certain objectives.

For example, a ward in their jungle near the Blue Buff would show you that the enemy Jungler and/or Mid is currently not killing it and it is somewhat safe to steal it. At the same time, if the ward shows you both their Jungler and AP Carry are at the Blue Buff, it is safe to do a 3/4/5vs2/1 team fight on bottom since you know they will be receiving no reinforcements.

Seeing the map just allows you to do/access/defend/attack safer, smarter, more efficiently.

Solution 2:

You don't have to have vision on the entire map. However, there are key points on the map where you can drop a ward to see incoming ganks or to have knowledge of what exactly the enemy team is trying to do. Having vision can easily save a team member from an enemy gank or allow your own team to counter gank a lane. It also makes it much easier to take an objective, if you see the enemy jungler up top lane/jungler then it can be an easy time to dragon without fear of an enemy smite.

Here are some key points to use Clairvoyance on:

Clairvoyance is no longer mandatory on a support champion, but is a very strong alternative.

The goal of Clairvoyance is to instantly provide information from any location on the map. As such, it is important to use Clairvoyance frequently, but still at critical areas. Spamming Clairvoyance at every cooldown can be as useless as never using it and depending on the stage of the game, one would focus Clairvoyances at different areas of the map.

Pre-minions: The very first Clairvoyance should be aimed on the opposing fountain (you want to use this immediately upon connecting), this allows for any obscure items to be visible and shows how fast the enemy team is mobilizing. The second Clairvoyance should be aimed to scout out where the enemy is going.

Pre-15 minutes: The third CV is always aimed at jungling routes, but in order to do this, one must understand jungling routes, speed and pattern. This is something that only playing a few games with competent jungling players or playing a few jungle games of your own will teach. Constant CV on the opposing jungler means it is impossible for him/her to gank without some warning and with good ward placement, it can be nearly impossible to gank. At this stage, knowledge is key and that knowledge starts with where the enemy jungler is. Junglers practically control the inertia of the game as they are the ones that make ganks happen, steal buffs and secure global objectives.

15 minutes and beyond: After countless CVs and many deaths/kills, both teams will likely start to work towards upcoming Dragons/Blue buff/Red buff/Baron. Simply having a CV is not enough and it is important to supplement it with numerous wards on key points.

Source: Solomid

Here are some good locations to green/purple ward throughout the game:

Source: Flatline

You will want to place the purple ward at Baron after the laning phase. You want a purple on dragon to clear any enemy wards, but this becomes less important when you have an oracles on the team. Try to keep dragon warded early since it is one of the earliest objectives teams will group up for.

Solution 3:

Map visibility is important to avoid ganks, or catch other players potentially out of position. If you have vision on two of three players in the top half of the map, that could give your team a free dragon or the ability to push an undefended lane without worry for a gank. Amazing vision over the map can also prevent people from juking away while chasing. Map Vision and awareness are some of the most important keys to winning in League of legends.