Never give a toddler a choice between a good option and a bad one. In other words, don’t ask, “Do you want to get dressed?” Instead, say, “Do you want to wear the red shirt or the blue shirt?”

My father-in-law learned this the hard way when, looking at an impossibly high pile of hot French fries in front of a small body, said, “can I please have one?” and got a fast, “No.”

While we don't like to infantilize partner, we also shouldn't allow partner to make a bad choice in the auction. Too many times, players make bids that I would describe as “inadvertently invitational.” When you make one of these bids, you are allowing partner to make a bad choice.

Unfortunately, a lot of players only realize a bid wasn’t forcing when they see their partner’s pass card. Even then, I sometimes see the player who invited yelling at their partner for passing. 

One key thought is that there are very few auctions where repeating a suit that’s been bid is forcing (particularly if you exclude 2/1 Game Forcing auctions).

Lets look at a common one:
You, South, hold:

AKQ654

2

AJ5

QJ4

The auction goes: 

West	North	East	South
	1	Pass	1
Pass	2	Pass	?

Many players will bid 3, but that is a bid that can be passed. If you aren't sure whether partner will find your next call forcing, it’s better to bid either 3NT or 4 to simplify the auction. There IS a call that would be forcing— 3 which is somewhat articifial (not a convention, but it doesn't have to be a real suit) and forcing. It may still be difficult to figure out whether you belong in spades or notrump later, but the 3 bid gives your partner another opportunity to raise spades. 

Here's another common one players get wrong: 

You, South, hold:

A543

KQ10

5

AKJ94

The auction goes: 

West	North	East	South
			1
Pass	1	Pass	?

Point count afficionados will say, "17 HCP is an invitational bid". I say, "Yuck!" If you bid three spades, your partner will pass with a variety of minimums that make game virtually laydown: 

KJ109

84

J432

Q76

is a terrible hand which would be an easy pass over 3. You might make an overtrick in 4. Don't give partner this bad choice. Heck, even if your partner has a sub-minimum: 

K10762

765

432

87, you have a chance to make a game (possibly with an overtrick!). 

 

This example is a matter of hand evaluation, but the broader point applies.

Before you bid, picture partner debating whether to bid or pass. If you will be mentally screaming "Don't pass!" You probably shouldn't make an invitational call.