He was hiring the attack net OUT
Not renting it IN.
FFS the BBC article on this was more in depth and accurate overall than the bolloxed pile of fetid dingo kidneys that's been posted on El Reg.
https://www.bbc.co.uk/news/uk-46840461 - also goes into more depth about the german charges
https://www.bbc.co.uk/news/uk-england-surrey-41115800
https://www.telegraph.co.uk/news/2019/01/11/briton-knocked-entire-country-offline-cyber-attack-jailed/
In any case, he was a skiddie not a hacker.
https://www.zdnet.com/article/hacker-bestbuy-sentenced-to-prison-for-operating-mirai-ddos-botnet/