As brought in the original halachic sources:
מַתְנִי׳ אֵין פּוֹדִין אֶת הַשְּׁבוּיִין יָתֵר עַל כְּדֵי דְּמֵיהֶן, מִפְּנֵי תִּיקּוּן הָעוֹלָם. וְאֵין מַבְרִיחִין אֶת הַשְּׁבוּיִין, מִפְּנֵי תִּיקּוּן הָעוֹלָם. רַבָּן שִׁמְעוֹן בֶּן גַּמְלִיאֵל אוֹמֵר: מִפְּנֵי תַּקָּנַת הַשְּׁבוּיִין.
MISHNA:The captives are not redeemed for more than their actual monetary value, for the betterment of the world; and one may not aid the captives in their attempt to escape from their captors for the betterment of the world, so that kidnappers will not be more restrictive with their captives to prevent them from escaping. Rabban Shimon ben Gamliel says: For the betterment of the captives, so that kidnappers will not avenge the escape of the captives by treating other captives with cruelty.