Jesus man this is pretty simple.
You go to work EVERYDAY, it learns that you go to work everyday, it will tell you traffic before you leave at 8AM, you can specify your work address so it knows for sure the address or you can let it learn on its own.
If you have a meeting along your day in your calendar with an Address it will tell you the traffic on the way when it's close to the meeting.
I'm not sure if your being purposefully obtuse, or what cause this has been explained many times throughout the thread.
The way you explained this is about 30% accurate, FYI. But that's not your fault.
There are three things we're talking about here. I'll talk about them in pieces and give them my own naming so as to separate them clearly.
Google Now - Predictive Traffic
Pops up a card with a map showing traffic between destination points. If you're at Point A it will show you traffic to Point B, and vice versa. This happens automatically, you are not required to do anything to make this start happening (unless you disabled the card). However, it will only get these points exactly right if you set the two addresses (i.e. Home and Work) in your Location settings. What I found is that without the addresses, it took a more general view; for example, I live in Bothell and work in Seattle, so it did a navigation from city to city rather than from even approximate addresses. When I gave it the addresses it then gave more accurate results. It MIGHT have done better with more time, but I would then consider that a deficiency since GPS knows my exact start and terminating locations.
It seems to pop the card regardless of the time of day and just checks traffic conditions throughout the day regardless of use. This is a downright battery killer if you're not on Wi-Fi. Like right now I'm sitting at home on the weekend, no work, yet it's showing me the work commute.
Google Now - Scheduled Commute Traffic
Pops up a card with a map showing traffic between your current location and where you need to be based on what appointments are in your Google Calendar (it may also look at your Mail calendar, but it won't look at other calendars, i.e. Touchdown. I don't use the Mail calendar because it gives too much power to the employer to literally wipe my entire phone. If I get a Nexus 7 I will test this because then it won't matter). This card can often confuse with the other card if the infrastructure in your area is poor.
For example, there are technically three roads I could take to get to work. One is shorter but has a toll that I refuse to pay, so I take a different freeway which ends up being longer but depending on what time I leave may end up being basically the same time to get there. Predictive Traffic learned that I repeatedly take this route and so will show me the traffic along the alternate freeway, but the Scheduled Commute Traffic will *always* pick the shortest route even if it's not what you want to do and even if functionally there is another route that would get you there at the same time without paying the toll. Just the other day it told me to take the toll bridge and pay $3.40 to get to Seattle in 30 minutes rather than just take the I-5 to get to Seattle in 30 minutes. Huh?
There's currently no way to give Google Now instructions to avoid tolls or avoid highways, so I don't use this that much at all.
Google Now - Scheduled Commute Notifications
This is a cool feature but fundamentally flawed, again, based on poor infrastructure.
Using the Scheduled Commute Traffic logic, this will pop a notification to you and "guess" how long in advance you should leave your current destination to get to your final destination based on assumed travel time given all factors detected. The problem I found is that in Western Washington it's wrong 100% of the time because the traffic conditions fluctuate too fast for Google to keep up with. This is because the infrastructure is so bad that there aren't ways to get around problems on the freeway. The I-5 is especially a problem.
For example, from my location I have to drive 10 minutes north on 405 to get to 5 south. During that 10 minute drive I might very well be looking at normal flowing traffic on the 5, but let's say a bus enters the freeway. It has to jam up traffic cramming over to the express lane before the flow improves again. Multiply that by 5 (since we have frequent buses), add in taxis, carpools, motorcycles, and cops and you end up with a problem within minutes. By the time I get there, it's heavy traffic. Another problem is accidents, if there are ANY accidents on either side of the freeway, traffic will choke horribly and suddenly, between people who don't know how to react and look-e-loos. Again, there is no way to avoid this catastrophe in certain stretches and there aren't enough offramps for alternate travel.
So assuming the traffic flow remains consistent, the estimate is accurate, i.e. in a better infrastructure, I should be able to reach Seattle in no more than 30 minutes. But because the infrastructure is poor and the traffic flow fluctuates so rapidly that Google can't keep up with it, it will tell you that leaving 30 minutes early is perfectly acceptable but your commute ends up being an hour. (mind you, this is a 19-mile distance). In a metro like San Diego where they have invested many millions of dollars developing a freeway system that properly manages traffic, this estimate is probably spot on (didn't get a chance to test it before I moved out).
The other things Google Now does:
- Weather card for forecasts
- Public transportation schedules as you get near to or pass bus stops and terminals
- Locations to check in (Google Latitude/Google+) as you pass them, restaurants, bars, etc.
- Sports scores and outcomes based on frequent searches for the same (Have never seen this because I don't search sports and it doesn't apparently count boxing)
