Some transits are easy to categorize automatically. If you have a stable, isolated star with steady brightness over time and then a single well defined transit, that's easy to automate. But not all stars are quite so cooperative. A lot of stars have variable brightness or are in multiple star systems. Those variations in brightness can be much greater than the transit signal, but humans are very good at pattern recognition and can pick up on those signals where computers would have a tough time.
You can go to https://www.planethunters.org/ to look at Kepler data right now to see what it looks like. If you can automate finding every single transit a human can in that kind of data, please do so.