In the third reading of our parsha the floodlights turn from Avraham to the minor character of Lot, who accompanied Avraham and Sarah since they left Haran. This is an opportunity to try and understand who Lot is and his character.
The argument between the Lot's and Avraham's shepherds causes Avraham to make the following suggestion
אַל נָ֨א תְהִ֤י מְרִיבָה֙ בֵּינִ֣י וּבֵינֶ֔ךָ וּבֵ֥ין רֹעַ֖י וּבֵ֣ין רֹעֶ֑יךָ כִּֽי אֲנָשִׁ֥ים אַחִ֖ים אֲנָֽחְנוּ. הֲלֹ֤א כָל הָאָ֨רֶץ֙ לְפָנֶ֔יךָ הִפָּ֥רֶד נָ֖א מֵֽעָלָ֑י…
Please let there be no quarrel between me and between you and between my herdsmen and between your herdsmen, for we are kinsmen. Is not all the land before you? Please part from me;
Lot accepts Avraham's suggestion, knowing that in a time of need, if there will be one in the future, Avraham will be at his side – as he promised
אִם הַשְּׂמֹ֣אל וְאֵימִ֔נָה וְאִם הַיָּמִ֖ין וְאַשְׂמְאִֽילָה.
if [you go] left, I will go right, and if [you go] right, I will go left."
As Rashi explains
Wherever you dwell, I will not distance myself from you, and I will stand by you as a protector and a helper.
This is exactly what happens later, when Lot gets captured by Amraphel, and Avraham comes to save him.
Lot looks up and sees the lower Jordan Valley, with its rich water sources, and chooses to live in Sodom & Amora – Which were like "God`s garden like Egypt", before being overturned