T-spin commitment is one of the leading causes of death in multiplayer Tetris. It generally occurs for players who are fairly new to creating T-spins. When setting up a T-spin right after completing a T-spin double (TSD), players may find that the T piece is near the end of the bag, only to realize this fact after it is too late. This phenomenon is known as being T-spin committed.
It is generally known that creating T-spins in quick succession is one of the keys to being a well rounder player. In order to make a T-spin, you generally need at most 6 pieces (fewer if you are building TSDs on top of garbage). One can then conclude that you will have many "throw away" pieces if you try to make many consecutive T-spins.
What to do?
There are several ways to prevent this from happening:
Using many previews - By making use of your previews, you can abort a TSD setup right before setting the overhang. A general rule of thumb could be aborting overhangs if you do not see a T piece in your Hold box or your next three previews (the amount of previews can be increased depending on how comfortable you are with your previews)
Using T-spins in moderation - The existence of T-spins does not make Tetrises entirely obsolete; just by watching pros play, it is easy to see that Tetrises are included in their repertoire. A ratio of one Tetris per two T-spins is a decent strategy, but should in no way be strictly followed. (The more consecutive TSDs you make, the more likely you are to get TSC'ed in the long run)
Learning to bail - So you've made the overhang already, only to realize the T is not coming (soon). The best solution would be to downstack the setup and create a TSD elsewhere.
Flat Stacking - Like being T-spin committed, flat stacking involves "throwing away" pieces. However, flat stacking is more efficient because you are clearing lines, thus keeping a low stack.
Look at the first frame of each fumen diagram, and redraw the garbage on a separate fumen.
Using the pieces in order from top to bottom, arrange them to prevent yourself from being T-spin committed. Click on the next frames to see the solutions to each problem. Note that there can be several solutions to a problem, as long as you meet the criteria of clearing a TSD at the end.
Bonus - Redraw the fumen of the diagram at the very top of the page. Use the same pieces to make the first TSD (Z,S,I,T) just like the diagram, but then redo the remaining part of it to avoid being T-spin committed. Use the same piece sequence as the diagram (Z,O,J,L,S,I).