For months, MBTA riders have had to endure more than 100 speed restrictions, slow zones and extended shutdowns for repairs. That's raised questions over why the system never seems to improve, despite all the work that has been done. Now, the reports commissioned by the T help explain why.

The problems lie with unclear responsibilities for the MBTA’s maintenance workers who were also inadequately trained to do the job properly, according to the reports from Carlson Transport Consulting and the T’s own safety department. The roles and responsibilities are especially unclear for those in charge of track inspections, the reports say.

That led to some employees conducting inconsistent inspections and missing documentation that left T officials with no idea how badly deteriorated the system’s infrastructure is. When the documentation problem was discovered earlier this year, it led to a sharp increase in slow zones until the true condition of the tracks could be verified.

The external report concluded that “the MBTA needs to refocus on activities that create and maintain a culture of safety.”

“While this news is difficult to hear and talk about, it's important to note that we've already begun addressing these issues,” T general manager Phillip Eng said at a press conference Thursday. “Initiating these audits proactively was an important step for us.”

Eng, who started in the job last spring, said the reports clearly show the most critical needs are: increased staffing, more training, developing clearly defined processes, quality control and more oversight. He said that he and his new management team, made up of veterans brought over from the New York City Transit Authority and the Long Island Railroad where he used to work, are capable of addressing the problems.

Eng acknowledged that bringing the T up to a state of good repair will take time, partly because more defects are found as T workers complete and document more inspections of the tracks. Fixing those defects in a timely manner, Eng said, requires disrupting service and shutting down parts of the system so that work crews have the time they need.

“I have to balance the need to provide service to the riders while we're trying to do the work,” he said. “How do you change the wheel while you’re riding the bike?”

Still, Eng promised that overall progress is being made and that service will eventually improve. He also said that no one would face discipline or termination for the problems documented in the reports.

Looking forward, he said his focus is on expanding maintenance, staffing and implementing more rigorous training standards.