I went for a ride on the Altamont Commuter Express train the other day, and from a user's perspective, it was a very frustrating experience, because absolutely everything about it is set up for the person who already takes the train every day and has been doing it for years, and thus knows everything about it. For a new customer, though, there's a distinct lack of information about certain important details, some of which the customer may well end up learning the hard way, by getting them wrong in ways that have a major impact on their trip.
The frustration starts with tickets: you must have a ticket to ride the train, but while some stations, such as Great America, have a convenient ACE-branded ticket booth where you can buy one, others, like San Jose, have no such booth and absolutely no information on how you can buy an ACE ticket. There are no ACE vending machines, though there are ones for Caltrain and Amtrak. There are absolutely no signs telling riders where to buy tickets, or indeed any signs related to ACE at all. Customers Just Gotta Know that they can buy ACE tickets at the Amtrak ticket window, unlike Caltrain tickets, which are only available from the Caltrain ticket machines. I'm not sure if you can buy them from Amtrak ticket machines too, but I wouldn't be surprised either way. I'm also not sure what one does at the Santa Clara station, where there are no station personnel at all.
But, assuming you actually managed to get your ticket and get on the train, the confusion and frustration is not over. Suppose you are going to Livermore and happen to be in the front car of the train. The train pulls into the platform... and then pulls past it! And then the door you're at doesn't open. Because, as everyone who takes the train every day knows, Livermore has a short platform and the front two cars don't open. And because everyone knows this, there's no need to announce it to everyone, so you don't find out until the train actually stops and you realize that it was in fact supposed to stop there, at which point you have to run through the train to hopefully jump out right as the doors are closing. And if you don't make it in time? I'm not sure what happens then, because the return train isn't till next morning (or Monday morning, if it happens to be a Friday), and the next stop has no public transit of any kind to let you get back to Livermore.
Things like station signage about tickets, or onboard announcements may seem like minor details, both to the commuters who use the service regularly, and to the people running the service. But they are crucially important to the lost and confused newbie who just wants to buy a ticket for the train, or to get off at the right stop. And while newbies are a small fraction of the customer base, everyone was a newbie themselves at one point. If ACE wants to keep maintaining a healthy ridership base, they need to make it easier for new customers to figure out how to use their service. You can't find out how great the train ride is if you never figure out how to get a ticket for it!