On Thursday I tackled bad reasons we might have turned down the rumoured £25 million bid for Jordan Amavi. Now let's have a look at some better ones:
Good reason no. 1: The risk to our promotion campaign is too great.
A very simple principle here - if selling Jordan Amavi and the accompanying disruption costs us our shot at promotion this season, then £25 million isn't worth it.
Estimates of the value of winning the play-off final for promotion to the Premier League hover around £200 million. There's a lot of money you can pass up in order to maximise that opportunity.
Even when a player is over-valued by a bid, the team might be going for a greater prize that overshadows the opportunity - think Leicester City holding onto Vardy and Mahrez in their title-winning season.
Now, obviously the calculation isn't quite that simple. We can't quantify the effect of selling Amavi, although the fact his current replacement is Aly Cissokho, who gave away two penalties in two games, strongly suggests it would result in dropped points.
So this links into the next good reason -
Good reason no.2: There's no upgrade available.
£25 million for Amavi would be great - if we could guarantee getting £25 million worth of player in return for the money. But transfers don't work like that. Look at the work of the Tomkin Times which concludes only 40% of transfers can be classed as a success.
If you can't immediately make an upgrade on the player, there's a points penalty (and therefore a financial penalty) incurred for making your team weaker.
With Amavi, it's hard to imagine Aston Villa can genuinely attract a left-back worth £25 million to the Championship, even if one can be successfully identified. Nor are there many left-backs more promising than Amavi in world football.
Now, admittedly that money doesn't have to all go on one player. A solid £10 million left-back - which would still be huge in the Championship - still leaves you with a healthy £15 million to invest elsewhere. But it's worth recognising that with any transfer fee there's an inevitable amount of wastage, which leads us to the next point -
Good reason no.3: The team doesn't need the money.
Again, a very simple one - if your team can currently buy any player it conceivably needs, there's not much point in selling.
Now, let's be clear, I don't think Aston Villa's resources are unlimited, even with Tony Xia's money. Nor do I like the idea of the club splashing cash needlessly. That's a sure-fire route to wasting your money and saddling the club with issues in the future.
But, linking to the previous point, if there's no way to use the money to improve team, unless the club's in financial trouble there's no reason to sell up. Over-valuation can be a relative thing - see the inevitable price inflation facing English clubs as compared to their European counterparts.
So all three of these reasons point to the same underlying principle - the potential risk is greater than the perceived reward for selling the player.
But there's another point to make here, which leads to one big reservation:
Reservation: Clubs should make sure they're always in a position to improve
All the reasons above are good reasons not to sell, but only if the club has no option to upgrade on the table. And football clubs should always be on the look-out for a better option and be able to move if an over-valued bid comes in.
Even if it's Chelsea and an over-valued bid comes in for Eden Hazard and the only name on the upgrade list is L. Messi, that option should be explored.
In the case of Amavi, Aston Villa should have a constantly updated list of possible replacements with a clear idea about which are open for purchase, at what price and how they should be valued.
More than that, the club should have a potential list for every single position and player. A team should never be trapped in a situation where a single player is indispensable - for a start, what happens if they get injured?
In the case of Amavi, maybe that process isn't in place at Villa at the moment. But I hope the backroom staff are scouting, having conversations with management and drawing up lists right now - not necessarily because they will sell him, but because the club should always maintain that option.