When they decide to loan out their existing players, of course they have considered the worst possibilities that they will face, one of which is as you said, being hit by injuries and so on. But we also have to look at it as an option, I mean when the players are in the squad but they don't play, then I think that's not a good thing, especially for the future of the player himself, especially if the player has good potential. The management must also be wise in seeing the opportunities for players on loan, especially in choosing a club that will provide many playing opportunities.
Yes maybe it is a disadvantage and advantage in itself, but in that choice there is the best choice, so choose the best of all choices. Players will also be happy if they are loaned out to a club that is ready to give them the opportunity to play, because for young players having many minutes to play is certainly a good thing.
And usually players who are loaned by a club to another club are players who have failed to enter the ranks of the core players in the squad built at that club. So that this player will also not be played much if he stays at the club if is not loaned out. But the club still has to pay even if the player doesn't contribute much. So lending players is indeed a good option for the financial condition of clubs who can get money from player loan agreements and players who are loaned will also have playing time at the club that borrowed their services. But the risks behind the profits are always there and it shouldn't be a problem that should be overly considered in these conditions.
Players who are loaned out are usually meant to increase their experience, as you said in this case when one club loaned out their players they did mean this to make them more able to develop because at the club they lived in could not compete with other players so their chances were very difficult to enter the main squad.
If the loan is successful and the player gets experience and more minutes, the hope is that this will make the loaned player more competitive when he returns but mostly if it is good sometimes it is also like a trial for the player and can use the permanent option after the loan is over.