Let’s face it: the least desirable game contract is five of a minor. If you’re in 5♣️ or 5♦️, you need to make 11 tricks, each of which is worth only 20 points. Often you’re better off in 3NT.

To be sure, there are times when 5♣️ or 5♦️ looks like the right contract. Consider this partnership in a duplicate game:

NORTH
     ♠️ K 9
     ♥️ K 5 4
     ♦️ Q J 8 7 5 3
     ♣️ 4 3

SOUTH (D)

     ♠️ A 8
     ♥️ Q J 2
     ♦️ A K 10 9 6 4
     ♣️ A 5

The bidding might proceed as follows:

South   North

1♦️   3♦️
5♦️   Pass

The contract will make.

But how about:

South   North

1♦️   3♦️
3NT   Pass

If clubs aren’t led, you can tap hearts for overtricks. If clubs are led, you get nine tricks for the same +400 or +600 score, depending on vulnerability, as you’d earn in 5♦️.
There are times to play in a minor-suit contract, especially in partials, and game contracts aren’t out of the question. Let’s change the South hand slightly:

NORTH

     ♠️ K 9
     ♥️ K 5 4
     ♦️ Q J 8 7 5 3
     ♣️ 4 3

SOUTH (D)

     ♠️ A 8
     ♥️ Q J 2
     ♦️ A K 10 9 6 4 2
     ♣️ 5

Now the original auction makes sense:

South   North
1♦️   3♦️
5♦️   Pass

The catch comes in knowing when to stop short of game. For a long time I considered a contract of 4♣️ or 4♦️ an insult and insisted, sometimes disastrously, on going to five. Here’s a hand from OK Bridge where the declarers came to their senses. East was dealing, with both sides vulnerable:

                           NORTH
                          ♠️ K
                          ♥️ J 10 9 5
                          ♦️ K 9 4
                          ♣️ K J 7 6 3

WEST                                            EAST
♠️ A Q 10 9 6 5 2                        ♠️ 8 4
♥️ Q 3                                         ♥️ K 8 6 4 2
♦️ Q                                            ♦️ 8 7 2
♣️ 9 8 4                                       ♣️ Q 10 5

                          SOUTH
                         ♠️ J 7 3
                         ♥️ A 7
                         ♦️ A J 10 6 5 3
                         ♣️ A 2

The bidding proceeded as follows:

East   South   West   North
Pass   1NT   2♠️   3♠️•
Pass   4♦️   All Pass

• Western cuebid asking partner to bid 3NT with a spade stopper

Opening lead: ♠️A

A few words about the auction. It’s fine to open 1NT with a six-card minor suit. Adding two points for the fifth and sixth diamonds, the South hand fits into the requisite 15-17 high-card-point range. West should have overcalled 3♠️, which North probably would have doubled for penalties.

The real lesson is that North-South stopped short of bidding 5♦️, and 4♦️ just made.

So beware of making a major deal over a minor contract.