An Army recruitment drive has faced "significant problems" - including a website that cost three times its budget and was 52 months late, a National Audit Office report has found.
Outsourcing giant Capita was awarded the £495m contract for Army recruitment in 2012 - but has failed to hit soldier recruitment targets every year since.
Capita admitted it had "underestimated the complexity" of the project.
The Army said it had "put in place a plan to address the challenges".
The NAO found the initial delay to the £113m website was caused by the Ministry of Defence, which failed to meet its contractual obligations to provide the IT infrastructure to host Capita's recruitment software.
The Army passed responsibility for developing the whole system to Capita in 2014, but "due to the complexity of the Army's requirements, system development was delayed even further", the report said.
And despite the website being finished in November 2017, the Army estimates there were 13,000 fewer applications between November 2017 and March 2018 than in the same period the previous year.
Capita has consistently missed the Army's recruitment targets, with the total shortfall ranging from 21% to 45%, the NAO said.
The Commons Defence Committee was told in October that the Army currently has 77,000 fully trained troops, compared with a target of 82,500.
The Army and Capita have introduced some "significant changes" in the last year, but none have resulted in enough soldiers being recruited, according to the NAO.
The report found it can take as long as 321 days for recruits to go from starting an application to beginning basic training, and that many drop out of the process while waiting.
A total of 47% of applicants dropped out of the process voluntarily in 2017/18, and both the Army and Capita believe the length of the process is a significant factor in this, the report said.
It added the project will not achieve its planned savings of £267m for the MoD.
Capita - whose 10-year contract continues until 2022 - said it had overhauled the "governance" on its contract and there were already improvements.
Nia Griffith MP, Labour's shadow defence secretary, said the Conservatives' "ideological obsession with outsourcing" had "driven up costs and resulted in the failure to recruit enough personnel to the Army".