Oh, where to start.... ;D
He's the spiritual godfather of the "militia myth" (although it pre-dated him), that Canadians are natural warriors and woodsmen, inherently superior to full-time soldiers of other nations (esp, Britain). His arrogance and public bragging about his awesomeness/British leadership incompetence got him thrown out of South Africa during the 2nd Boer War -- where he fought for the British because the Canadian commander wanted nothing to do with him.
Back home, he eventually cajoled his way into Minister of Militia and Defence under Borden. He worked hard to build up the Militia, at the expense of the Permanent Force, right up to 1914. With the declaration of war, he threw out the straight-forward mobilization plan built by LGen Gwatkin (Brit RegF; Chief of General Staff for Canadian Army) to gather troops at Petawawa for pre-deployment training. Instead, he sent telegrams to individual COs to get their troops to Valcartier....where they had to actually build the camp before they could even start pre-deployment training -- leaving little time for actual training.
Getting troops and equipment to Halifax, loading, and unloading in England was even more of a nightmare, because there was no plan, rhyme or reason to it.
Micromanaging; foisting poor equipment based on his personal preference; political interference and media muck-raking. He's got it all.
.....except one or more Victoria Crosses, which he felt he deserved for his South African exploits.
In effect, Sam Hughes is a role model for the "Mess-kit Militia" (which is why we can't amalgamate understrength units; the Reserves would lose way too many LCol/CWO positions, and then who would organize the Army Ball, campaign for new/old rank badges, claim to be SAS, and stuff) >