The Gemara in Chullin 105b says that leaving bread crumbs can increase a person’s vulnerability to poverty. Also, The Gemara in Pesachim 111b says that bran(parei) in the house causes poverty and bread crumbs in the house cause poverty.
What are the other things or actions which cause poverty?
Mishlei 10:4 writes:
רָ֗אשׁ עֹשֶׂ֥ה כַף־רְמִיָּ֑ה וְיַ֖ד חָרוּצִ֣ים תַּעֲשִֽׁיר׃
Deceitful scale cause poverty, But diligent hands enrich.
The mefarshim there explain this pasuk as a reference to merchants who try to cheat their clients, the end result will result with them becoming poor. (Refer to Ibn Ezra)
Also refer to Bava Metzia 33a - the Mishna there talks about a person retrieving a lost object that takes precedence over searching for an object of his father or teacher. The Gemara learns that one's own financial concerns come first. However it brings Rav Yehuda in the name of Rav who says:
ואמר רב יהודה אמר רב כל המקיים בעצמו כך סוף בא לידי כך:
And Rav Yehuda in the name of Rav says, anyone who establishes (such a way of life) for himself, in the end will come to that i.e. will endure the very poverty he seeks to avoid.
As Rashi and the Maharal assert, since such a person is constantly weighing up his financial situation and seeing if he will incur a loss, he will never come to act in a kind, benevolent way i.e. he will see himself as being exempt from acting charitably. Therefore he will become impoverished as a punishment and will be forced to rely on the generosity of others.
Orach Chaim 241:1
אחד מהדברים ששונא הקב"ה המשתין בפני מטתו ערום המשתין לפני מטתו ערום מביא לידי עניות
One of the things which HKB'H hates is one who urinates naked before his bed. One who urinates naked before his bed brings upon himself poverty.
אָמַר רַבִּי אֲבָהוּ, וְאָמְרִי לַהּ בְּמַתְנִיתָא תָּנָא: שְׁלֹשָׁה דְּבָרִים מְבִיאִין אֶת הָאָדָם לִידֵי עֲנִיּוּת, וְאֵלּוּ הֵן: הַמַּשְׁתִּין מַיִם בִּפְנֵי מִטָּתוֹ עָרוֹם, וּמְזַלְזֵל בִּנְטִילַת יָדַיִם, וְשֶׁאִשְׁתּוֹ מְקַלַּלְתּוֹ בְּפָנָיו.
On a related note, Rabbi Abbahu said, and some say it was taught in a baraita: Three matters bring a person to a state of poverty [as a divine punishment from Heaven:] One who urinates before his bed while naked, and one who demeans the ritual washing of the hands, and one whose wife curses him in his presence.
הַמַּשְׁתִּין מַיִם בִּפְנֵי מִטָּתוֹ עָרוֹם, אָמַר רָבָא: לָא אֲמַרַן אֶלָּא דְּמַהְדַּר אַפֵּיהּ לְפוּרְיֵיהּ, אֲבָל לְבָרַאי — לֵית לַן בַּהּ.
[The Gemara explains:] With regard to one who urinates before his bed while naked, Rava said: We only said this prohibition in a case where he turns his face toward his bed and urinates toward it; however, if he turns his face and urinates toward the outer portion of the room, we have no problem with it.
וּמַהְדַּר אַפֵּיהּ לְפוּרְיֵיהּ, נָמֵי לָא אֲמַרַן אֶלָּא לְאַרְעָא, אֲבָל בְּמָנָא — לֵית לַן בַּהּ.
And where one turns his face toward his bed, too, we only said this prohibition in a case where he urinates on the ground; however, if he urinates into a vessel, we have no problem with it since that is not considered disgusting.
וּמְזַלְזֵל בִּנְטִילַת יָדַיִם, אָמַר רָבָא: לָא אֲמַרַן אֶלָּא דְּלָא מְשָׁא יְדֵיהּ כְּלָל, אֲבָל מְשָׁא וְלָא מְשָׁא — לֵית לַן בַּהּ.
With regard to one who demeans the ritual washing of the hands, Rava said: We only said this statement in a case where he does not wash his hands at all; however, if he washes his hands and does not wash them with a significant amount of water, we have no problem with it.
וְלָאו מִלְּתָא הִיא, דְּאָמַר רַב חִסְדָּא: אֲנָא מְשַׁאי מְלֵא חָפְנַי מַיָּא וִיהַבוּ לִי מְלֵא חָפְנַי טֵיבוּתָא.
[The Gemara notes:] And that is not so, as Rav Ḥisda said: I wash my hands with handfuls of water and they gave me in reward handfuls of prosperity. [Apparently, in order to garner the benefits of ritual washing of his hands, one should use a significant amount of water.]
וְשֶׁאִשְׁתּוֹ מְקַלַּלְתּוֹ בְּפָנָיו, אָמַר רָבָא: עַל עִסְקֵי תַּכְשִׁיטֶיהָ. וְהָנֵי מִילֵּי הוּא דְּאִית לֵיהּ וְלָא עָבֵיד.
With regard to one whose wife curses him in his presence, Rava said: This is referring to a case where she curses him over matters relating to her ornaments, i.e., she complains that he does not provide her with jewelry. The Gemara comments: And that applies only when he has the resources to buy her jewelry but does not do so; [however, if he does not have sufficient resources he need not be concerned.]
This is also brought in Sefer haMidot - Mamon #32
There's another Gemara that says three things bring poverty: Cheap white wine, inferior bedsheets, and hiring servants and not supervising them..
But I couldn't find it, maybe someone can add..
Mishlei 29:3
וְרֹעֶ֥ה ז֜וֹנ֗וֹת יְאַבֶּד־הֽוֹן
One who keeps company with harlots, will lose his wealth.
Ralbag:
מי שנמשך אל התאוות ורועה זונות הוא יאבד הון אביו ויאבד ממנו קנין כל הון וכל שלימות אנושי
He who is drawn to lust, and keeps company with prostitutes, will lose his father's fortune, and will lose from himself the acquisition of fortune, and the acquisition of all human perfection.
1. The Kitzur Shulchan Aruch (151:1) writes; that as a punishment for masturbating and thereby discharging semen in vain, a person can sometimes be reduced to poverty.
וְלִפְעָמִים בְּעֹנֶשׁ זֶה, חַס וְשָׁלוֹם, בָּנָיו מֵתִים כְּשֶׁהֵם קְטַנִים, אוֹ שֶׁיִהְיוּ רְשָׁעִים, **וְהוּא בָא לִידֵי עֲנִיוּת
2. The Chafetz Chaim, at the end of his work, "Machaneh Yisrael", has an appendix, entitled "Davar Be'ito", where he chastises those who delay marriage, because they haven't found someone to pay them a large dowry. The Chafetz Chaim notes, that those who delay marriage are liable to succumb to the sin of masturbation, which leads to poverty, and therefore any financial gain he might have from the large dowry, will be offset by the financial losses incurred due to his sin.
In his words:
גם ידוע הוא מהספרים הקדושים, שעון זה (של הוצאת זרע לבטלה) גורם אחר כך לבוא לידי עניות, חס ושלום, ומי יודע עד כמה זמן יגזרו עליו עניות עבור זה. ואם כן מה יועיל לו אם יקח נדוניא יותר על ידי המתנתו, הלא יצא שכרו בהפסדו.
3. The Sefer Habris, by Rabbi Pinchas Eliyahu [Horowitz] of Vilna (Part I, 16:3) quotes a tradition, in the name of the Rokeach:
One who is habit of ejaculating in vain; even if he born in a good Mazal, it turns out to be him a bad Mazal. He will be a man who will not succeed in his days, and whatever he does in craft or commodity he loses… This is [a punishment of] measure for measure. He occupied his hands and violated his holy Covenant [of the circumcision], therefore, God will send the curse the shortage, in all that he does, until he is poor and destitute all his days.
In his words:
יש קבלה בידינו, והוא בדוק ומנוסה בנסיון, שכל הרגיל בעון הוצאת זרע לבטלה, אפילו אם נולד במזל טוב, מתהפך להיות לו למזל רע, ויהיה גבר לא יצלח בימיו, וכל אשר הוא עושה במלאכה או בסחורה הוא מפסיד. אפילו אם זהב בידו, מתהפך ברוע מזלו לנחושת, מדה כנגד מדה. הוא שלח את ידיו וחלל את בריתו, ברית קודש, לכן, בכל מעשי ידיו ישלח ה' את המארה ואת המגערת, עד שיהיה עני ודל כל ימיו. וזהו שאמר הכתוב (ישעי' ג יא) "אוי לרשע רע כי גמול ידיו יעשה לו".
