Deutéronome 1:12

But how can I alone sustain the labour, your sensuality, your evil thoughts, your words of strife, your offering one shekel for two?

your hardship as in “they are a trouble to me” [Isaiah 1: 14]. This is the hardship of making foolish people understand the Commandments.

your burden i.e., their demands for bread [Numbers 21: 5], and water [Exodus 17: 2] [cf. comment on Exodus 17: 2], and meat [Numbers 11: 4].

HOW CAN I MYSELF ALONE BEAR ‘TORCHACHEM’ (YOUR TROUBLE) ‘UMASA’ACHEM’ (AND YOUR BURDEN), V’RIVCHEM (AND YOUR STRIFE)? According to the simple meaning of Scripture, Moses our teacher alluded to them the three things which he told Jethro that he was doing for the people, as I have explained there. He now mentioned them to Israel by implication. He said torchachem corresponding to and I make known to them the statutes of G-d and His laws,, Verse 16. for it was a difficult “task” to teach those who had come forth from Egypt, the statutes and the laws of G-d, their meanings, interpretations, and secrets. He said masa’achem corresponding to the people come unto me to inquire of G-d, a reference to prayer, for he used to pray on their behalf. The word masa’achem is related to the expression: ‘v’nasatha t’filah’ (and thou lift up prayer); nor ‘tisa’ (lift up) entreaty or prayer in their behalf. [He stated] ‘v’rivchem’ (and your strife) which is to be understood in its plain sense — matters of judgments [because judges must rule when there is strife among people]. Moses continued to state: Get you men who are wise, and understanding, and known among your tribes — referring only to [the qualities of] judges. But he said unqualifiedly, and I will make them heads over you by way of humility.
Now Rashi quotes from the Sifre: 12. “‘Torchachem’ (Your trouble). This teaches that they were troublesome. If one perceived that his opponent was winning a litigation, he would say ‘I have witnesses to bring; I have evidence to present; I [exercise my right to] add judges to you [thereby increasing the size of the court].’” But I do not know [the validity of] this law that one of the litigants should have the right to add judges above [the usual number of] three in cases concerning monetary matters, and surely he has no such right after presenting his case before them and perceiving that his opponent was winning the case! For, had he voluntarily accepted upon himself a relative or an unqualified person as a judge, he could indeed retract prior to the rendering of the final judgment, but from those qualified to judge he cannot retract [his acceptance]! Perhaps we can deduce from here the principle that a man can say, “I choose two judges and you choose two other ones, and they [i.e., the four judges] will choose one more, be divisible evenly;” it must have an odd number of judges to assure that, in the event of a split, there would not be a tie vote (ibid., 2a). and let the suit be decided by five or more judges,” just as the Rabbis have said: 2:13). “A suit decided by five [judges] is not comparable to one decided by ten [judges].” Although three judges [have the power to] compel parties to come before them for judgment when one refuses to be bound by their decision, yet if one [of the litigants] desires to choose additional judges, he may do so, because it is similar to [the case of] one [of the litigants] who says, “Let us go to the main meeting place of the scholars [to bring our suit before them on the assumption that superior scholars are better qualified to judge],” in which case we accede to him, provided it does not entail [undue] hardship, for in such a case we have been commanded, Justice, justice, shalt thou pursue, [which the Sifre interpreted]: “Go to a reliable court,” and an increase in the number constitutes “a reliable court.” 144; Sanhedrin 32b. Now in the wilderness, wise men were available to them and the litigants could say, “Let us go before the officers of the thousands.”

טרחכם, your petty arguments which did not even involve financial claims.

ומשאכם, your bicckering involving the provision of the needs for the many.

וריבכם, and your mutual financial claims upon one another. He reminded them of all this in order that they should remember their sins. He hoped that the people repented their past conduct honestly, for in the past, in spite of Moses having told them that they would take over the land of Canaan without even having to fight for it, something that should have been their major concern seeing that they were in the desert. Rather than focusing on their major problem, how to get out of the desert into the promised land, they had wasted their time and efforts in the pursuit of petty concerns, undermining their inter-personal relationships in the process. Due to this interminable quarreling, Moses had been forced to appoint a large number of judges that had to exert authority over the individuals down to every 10 people requiring at least one such judge. This could only have been due to some character weakness, some pre-disposition to be quarrelsome.