non-standard transactions, fees are too low, miner's preference, etc. No one can really tell you the odds of it happening; generally miners do not actively exclude specific transactions and non-standard transactions should not happen if your wallet is functional. I vaguely recall there's one mining pool that mines non-segwit transactions exclusively.
For it to be never included in the block signifies that all of the miners collectively do not want to mine it and it's almost always because it is invalid or non-standard.**
what's a non-standard transaction?
could a fee be too low if I kept the default fee, using a good wallet? Or would it only happen if I lowered the fee myself?
Weeks.
What fee did you pay?
Possible. How much fees did you pay? The minimum fees for a good propagation is 1sat/vbyte and can increase depending on the mempool capacity (which I assume isn't the case). Poor propagation is not all that common anymore, what wallet are you using?
*Non-standard transactions can still be included in a block but they require explicit participation from a miner that is able to mine a block.
don't rememeber which transaction was it, it was either 1980sats for a 1262500sats transfer, or a 3936 fee for a 9900000 transaction..one or the other, using edge wallet.
is edge a recommended wallet, or is it just good for noobs?