Strengthen your teams by encouraging them to make decisions for the company based on facts and research - even if it's hard to hear
"The train has left the station" is probably the weakest excuse for pushing a product that has no future. Regardless of the phase, if you figure out that a new product won't achieve the profit targets, then you should kill the project as quickly as possible.
Strike unprofitable projects from your list
Make a strong impression on your team by setting a good example. Everyone will know that you practice what you preach.
For really important decisions, use two parallel teams
An example: The board of a client always assigns two independent teams with the job of developing a price strategy for the market launch of major products. This approach consistently provides the client the best possible results. When you're dealing with a multi-million-dollar product, the approach pays off immediately.
Make your teams share the responsibility for their decisions and recommendations
Team members should sign off personally on all milestone presentations, business cases and forecasts. Of course, no one will be held personally accountable when things don't go as planned, but each signature will make team members critically check interim results, ultimately improving the overall team results.
Beware of well-intended, but flawed incentives
Incentives gone wrong: In one company, project team members were given incentives to bring as many new products to the market as possible, regardless of quality. A major mistake!