Numerous attempts were made by Joseph Joffre, the French supreme commander, Sir Douglas Haig, Ferdinand Foch and the army commanders Henry Rawlinson and Émile Fayolle to co-ordinate joint attacks, which failed due to the recovery of the German 2nd Army from the disorganisation caused by the defeats in early July, disagreements over tactics by Haig and Joffre in July and August and organisational constraints caused by congestion behind the front, roads and tracks obliterated by Anglo-French artillery-fire becoming swamps when it rained and increasing German artillery-fire on targets behind the front line. Inexperience, unreliable machinery, guns, ammunition and an unpredictable flow of supplies from Britain, reduced the effectiveness of the British armies. Difficulty in co-ordinating attacks by the Entente armies and the large number of piecemeal attacks resorted to by the British, have been criticised as costly failures and evidence of muddle and incompetence by the generals. The French Sixth and Tenth Army armies had similar difficulties and severe strain had been put on the German 2nd and 1st Army (formed on 19 July), forcing them into a similar piecemeal defence.