Averaging into a trade as part of a pre-determined strategy, and with pre-determined limits is quite acceptable (for me) - I regularly do it when trading divergence between index futures, where the trades that initially go against me are the ones that I make the best return on.
This is quite different to averaging into a trade that is going against you, in an ad-hoc manner in the hope that you will recoup your losses (yes, I've done that too, but thankfully not in a while!)
It is better to be right or wrong with a trade - for most people averaging in on negative initial results just complicates matters and increases the probability of a big loss, but that's not to say it can't be a useful strategy if you know what you are doing.
This is quite different to averaging into a trade that is going against you, in an ad-hoc manner in the hope that you will recoup your losses (yes, I've done that too, but thankfully not in a while!)
It is better to be right or wrong with a trade - for most people averaging in on negative initial results just complicates matters and increases the probability of a big loss, but that's not to say it can't be a useful strategy if you know what you are doing.