The research showed the issue is most prevalent in remote work settings, where 14 per cent of engineers were classified as "ghost engineers" compared to six per cent of office-based staff. The study evaluated productivity through analysis of private Git repositories and simulated expert assessments of code commits.

Major tech companies are significantly impacted, with IBM estimated to have 17,100 underperforming engineers at an annual cost of $2.5 billion.

Across the global software industry, the researchers estimate the total cost of underperforming engineers could reach $90 billion, based on a conservative 6.5 per cent rate of "ghost engineers" worldwide.

One engineer said that some of the problem was the way that management structured or rewarded poor performance.

"I worked at Apple, and I didn’t have a huge amount of kernel experience, but I was half of the team implementing sandboxing, so we had some pretty far reaching kernel changes. I ended up committing a lot of bad bugs. I fixed basically all of them. It gave me a fantastic P2 fix rate. I got an award for it (and a free wheel of cheese!). I don’t think it was actually a good year for productivity. I committed a lot of bad code, and patched it all up again."